Sierra Bullets 6.5 Creedmoor Load Data

download-6-5-creedmoor-data-button

sierra-bullets-6-5-creedmoor-diagramTest Specifications/
Components

Firearm Used: Universal Receiver
Barrel Length: 24”
Twist: 1-8’’
Case: Hornady
Trim-to Length: 1.910’’
Primer: Winchester WLR

Remarks:

Developed in 2007 by Dennis DeMille and Dave Emary, the 6.5 Creedmoor is a shortened and improved 30 TC cartridge case that was inspired by the .308 Winchester design.  This short action design was created to maximize case capacity and a wide range of loading lengths, while still fitting in standard short action magazines.  With the correct twist barrel, the versatile 6.5 Creedmoor can take advantage of the wide range of bullet weights available in 6.5mm.  Reloaders should keep in mind that the 6.5 Creedmoor works best with medium to medium-slow powders such as H4350, Varget, Win 760, and RE-17.  The light recoil and adaptability of the efficient 6.5 Creedmoor cartridge has already proven itself in high power, precision rifle series and benchrest competitions.  Couple that with respectable barrel life and its intrinsic accuracy potential and you have a recipe for success which should insure its legacy for decades to come.

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INDICATES MAXIMUM LOAD – USE CAUTION
LOADS LESS THAN MINIMUM CHARGES SHOWN ARE NOT RECOMMENDED.

2-sierra-bullets-6-5-creedmoor-dataINDICATES MAXIMUM LOAD – USE CAUTION
LOADS LESS THAN MINIMUM CHARGES SHOWN ARE NOT RECOMMENDED.

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INDICATES MAXIMUM LOAD – USE CAUTION
LOADS LESS THAN MINIMUM CHARGES SHOWN ARE NOT RECOMMENDED.

4a-sierra-bullets-6-5-creedmoor-dataINDICATES MAXIMUM LOAD – USE CAUTION
LOADS LESS THAN MINIMUM CHARGES SHOWN ARE NOT RECOMMENDED.

5-sierra-bullets-6-5-creedmoor-data

INDICATES MAXIMUM LOAD – USE CAUTION
LOADS LESS THAN MINIMUM CHARGES SHOWN ARE NOT RECOMMENDED.

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INDICATES MAXIMUM LOAD – USE CAUTION
LOADS LESS THAN MINIMUM CHARGES SHOWN ARE NOT RECOMMENDED.

7-sierra-bullets-6-5-creedmoor-data

INDICATES MAXIMUM LOAD – USE CAUTION
LOADS LESS THAN MINIMUM CHARGES SHOWN ARE NOT RECOMMENDED.

Posted in Reloading | Tagged , , , , , , | 46 Comments

45 Colt Report

Written by Sierra Bullets Ballistic Technician Philip Mahin

Last time we spoke, I said I would give you an accuracy report from my Henry 45 Colt shooting our #8820 240 gr JHC Sports Master so here it is. As much as I try to keep the thing cool between shots, it does heat up after a 5 shot group. I have realized if I put the gun aside after every shot and let it cool back down to ambient temperature, it won’t open groups as bad. I could get three off before it ever got warm enough to make any difference but it is a hunting gun and I shouldn’t need more than the first one, right?

The first three shots are usually close, within an inch and a quarter or so and after that, they go a little wild. My notes list a nine shot group inside of two and three quarter inches. Also my notes list rapid fire three shot groups that average two inches from my sitting position.

I was able to get one group that measured less than an inch from four shots off my bench. It went off the paper target and went into the cardboard backing so I saved it to show here.

By the way, these descriptions are running center to center and shot at fifty yards. One other thing to remember, the front sight brass bead covers roughly six inches in diameter at fifty yards.  It is original to the firearm and it worked well with the ghost ring rear sight I installed. Speaking of the rear sight, it wears an XS Sights ghost aperture designed for the Marlin 336 because the hole spacing matched. My shooting keeps the aperture bottomed out and almost all the way to the left but that keeps me well inside the top half of the front sight.


Even though they say the gun alone weights six and a half pounds, it is easy to shoulder fast because it is short and handy. It is easy to carry because it balances so well with the hand just forward of the trigger guard. There is no safety but the hammer will rest down on a full chamber because of a transfer bar system. To make it fire would take the hammer to be re-cocked and then the trigger pulled. I applaud them for this kind of system because in an ever-increasing world of products that dumb us down, this puts the control back into my hands where it should be in the first place.

The brass life has exceeded my expectations as I’m on reload number seven so far. I’ve not been kind to them either with higher than normal for the cartridge pressures. The primer pockets are still tight and the case mouths are still flexible. I have needed to trim them but that is because the brass is moving 0.01” or more from fired to full length sized.

I am glad I was able to purchase this firearm. It has performed well for me and I enjoy using it. I made the mistake of saying that ‘someday, I’ll shoot the barrel out and…’ and before I could finish, the 800 room was a roar with laughter.

Till next time, have fun and be safe shooting.

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My Philmont Adventure

Written by Sierra Bullets Ballistic Technician Rich Machholz

This story starts way back in February. Actually before that even, during the SHOT Show to be specific. During that time frame Mr. David O’Neill from the Boy Scouts of America approached our President Mr. Patrick Daly for assistance at The Philmont Scout Ranch and Training Center near Cimarron New Mexico. Since I spend one week a summer teaching reloading at Trinidad State Junior College in association with their NRA Summer Gunsmithing courses if I could get one week to follow the other in no particular order it would work out very well. As luck would have it The Philmont opportunity was the week before the Trinidad class. Perfect!

I had no idea of what to expect but 6 years of past experience at Trinidad teaching Reloading A-Z and 25 years of Technical Assistance here at Sierra Bullets has conditioned me to all levels of experience when it comes to reloading. Still it bothered me that I had absolutely no idea of the format other than other people from the industry would be there to assist also. I didn’t have a plan. To make things worse I’d never been past the NRA Whittington Shooting Center and had no idea of how many hours of driving time I was looking at. So my plan was pretty simple, get through Kansas City after morning rush hour but before the noon rush, then turn up the wick and get some miles under us. By this time I did have an idea of the time frame and it seemed like about 15 1/2 hours total door to door. We gave the house sitter last minute instructions, told the dogs good bye and headed west. The wife was still trying to pack her suitcase as I was dragging it to the car. Go figure.

Luckily I-70 is pretty simple to navigate through Kansas City and we missed the major traffic so the first part of our trip was good. There is a short section of toll road to pass through and then it’s hello Kansas.

Now I’ve heard it said many times that the best time to go through Kansas is during the night. Nothing could be further from the truth this year. They have had plenty of rain and the hills are vibrant with color from wild flowers and all the various greens. The familiar tans and grays of scorched earth were not there this year replaced with the abundance of prairie fauna. I was relieved to see Oakley Kansas coming up which would be our stopping point for the day. No more driving into the late afternoons bright setting sun.

After a good nights rest at Oakley we headed west southwest on Highway 40. We gained an hour around Sharon Springs Colorado and continued on to lunch at La Junta Colorado by following highway 385 which also loosely follows the Santé Fe Trail. There is an 80 mile stretch on 385 from La Junta to Trinidad that is pretty isolated and no services. Normally it is desert to a Missourian like me but this year it is green and lush and the cattle are slick and heavy. It was a beautiful scenic drive for a change. We jumped on I-25 and headed south at Trinidad and encountered a huge rock slide in the Raton pass that closed the north bound lanes. It was still closed a week later and is probably still closed three weeks later as some of the boulders were much larger than a good sized house. Finally, over the pass, we head down the other side past Raton on I-25 looking for NM highway 64 which will take us past The NRA Whittington Center, Cold Beer NM and ultimately to Cimarron New Mexico where we turn left on Highway 21 taking us to the Philmont Base Camp.

Okay we are in the area but where is the main office? The Philmont Base Camp is huge. A maize of familiar brown buildings, a huge lodge and another group of buildings that form the center of the Base Camp. Signage is plentiful, comprehension not so much and after asking a couple of times we finally get to the office, meeting several very pleasant people on the way. Our very busy host Mr. David O’Neil, gave us a brief overview of the Ranch and made sure we did indeed have a roof over our heads for our visit. Hey … it’s a scout camp! All I saw was tents, lots of tents and I found out my wife had no intentions of sleeping in a tent on this trip. So, as we pass through the main camp area we say good bye to literally 100s of tents that are waiting for the onslaught of scouts due in at the end of the week. Ten miles further we arrive at the main gate to the ranch that is hosting us and we are greeted by 10-12 mule deer just inside the gates. As we proceed down the long drive past large corrals to the main lodge located in a valley, a flock of turkeys come strolling through the short grass pasture only slightly concerned by our presence. Wildlife is present and abundant, the silence is deafening.


Our lodging was at the UU Bar Ranch and the accommodations were top notch, staffed by a very gracious group of people.  In the warm months fishing is a big draw with angling for trout, bass and pike besides hiking and other outdoor activities.  In the fall upland game and big game hunts are on the agenda.

By now I have to admit that I had a certain amount of anxiety. All I knew was that me and several of my industry peers were going to be present to help train the “trainers”. It was hard to rest but as the other members of the team arrived I began to relax. Breakfast at 6:30 AM, assemble by 8 AM were the instructions and bring water bottle, rain jacket, camera and any training materials. I had noted the altitude earlier at 7000+. We divided up into 4 groups. My group picked a sack lunch and loaded into 4X4 Suburbans headed out to Sawmill Camp. And what a trip it was, Grant Reigelman was our driver and he made sure to point out landmarks and points of interest all the while keeping at least 2 wheels in contact with the not so civilized trail. (Even the wildest imagination could not envision this as a road.) The dozer operators who cut and maintain these “trails” must be fearless! On one side you had no room and the other, well lots and lots of room, all down usually, waaay down.

Grant said Sawmill was at about 10,500 feet and the “staffers” trekked to the camp a few days earlier following well marked trails. We finally arrived after more than an hour of negotiating trails and were greeted by some jubilant campers.

So after introductions all around we head to the main camp building. Sawmill Camp in two buildings, living quarters and a loading “shack” which is actually pretty darn nice, roomy and well light.

The staff was comprised of 9 guys, the oldest was 21 maybe and the youngest 16. All were at least familiar with reloading and the equipment on hand. We established that we were to load 30-06 and 150 grain bullets with Hodgdon H4895 and we decided that 42 grains would be a user friendly load. There were 7 of us industry members so we each took a staffer through each phase of the reloading process at least twice individually to make sure they fully understood the process and were comfortable with the process. Then each staffer loaded a minimum of 20 cartridges to be fired later in the day.

Someone called lunch and got no argument from me. By this time I was just getting adjusted to the extreme altitude and it was evident that a fat flatlander from Missouri couldn’t breathe in the rare air of New Mexico at 10,000+ feet of elevation, at least not right away. I had picked ham for my sack lunch and I was amazed at how it was packed. The bread was individually packed, the ham in another bag, lettuce/tomato in another, soft drink, apple, chips and a cookie plus condiments. Life is good.


After lunch we went back to the loading shack to finish loading our 20 rounds each. When that was completed the staffers trekked to the rifle range while we rode – most of the way. A fallen tree was the final obstacle. More deep hard breathing as we walked a short distance to the shooting range. The shooting area was a 40×40 covered area with 4 nice shooting benches on one end, ground level on one side and elevated about 6-8 feet on the other side.

The range itself was short, only 100 yards with 50 and 75 yard targets as well. Ruger furnished the firearms and they were M77 Guide Guns in 30-06. Earlier I had questioned the caliber choice and lobbied for the light 42 grain load. The Guide Guns do have a muzzle brake but even if they didn’t it wouldn’t have dampened the enthusiasm of the shooters. All loads went bang, functioned without a hitch and targets were hit. Safety was paramount as it should be but the staffers policed themselves every bit as diligently as any Range Officer you have ever encountered. Our job completed we said our good byes and left the staffers with some seriously dirty guns and lots of empty brass to reload.

On the way down I had lots of questions. Grant pointed out that last year (2016) over 27,000 kids participated in the Philmont Camping and Training Adventure Programs, nearly 12,000 were new to a shooting discipline. He was also quick to point out that Philmont is the only major camp with a shooting program. Sawmill is the centerfire camp but a few days trek away is either black power, shotgun, traditional muzzle loader or frontier black powder camps. Those kids fired 38,617 black powder shots, in excess of 22,000 30-06 cartridges and over 18,000 shotgun shells. The Frontier camp shot over 36,000 38 Special cartridges. There are many other camps scattered over the 140,000 acre high country ranch. In all over 123,000 shots were fired using nearly 600 pounds of Hodgdon powder! That is a lot of shooting in just a few short weeks.

The next day was just as early but we visited other back country camps that were closer with easier access. The scenery was beautiful and the trails nearly as challenging but not nearly as long. In all we visited 4 more camps. The staffers were dressed in period costumes typical of the time the camp represented. That is except for the Harlan Camp which is the shotgun camp. They had just received new Browning O/U Citouri 12 gauge shotguns and Skler Switlik had just come to rebuild their Promatic traps so it was a big day plus Shawn Wosniak had done his magic to their MEC loaders. They were eager to show their camp off.

I learned a lot on this trip. First, be prepared to walk much more than you do at home. You park your car and walk to the dining hall, infirmary, Tooth of Time Traders or the offices. There are handicapped parking spaces but you’d better be handicapped if you use them.
Tooth of Time Traders is a great place to shop for quality outdoor gear at reasonable prices.

The logistics of Philmont is staggering. They have over 300 kids arriving each day and after the first few days that many kids leaving as well. There are also 300 coming back from trekking each day. How do you keep track of 1000 different teenagers on a daily basis and consider that the first 300 are there for several days with more arriving each day and none of them have tracking collars! It would be hard enough if they were in town but they aren’t. They are not even close to a light. They are on the trail in the high back country wilderness, on their own come rain or shine, heat or cold with only their own two feet for travel. But then they are Boy Scouts and prepared.

So when they embark on their trek they are carrying everything they need including food and water. Again the logistics of all that just stagger me! At peak time they will have 5000-6000 kids on the trail each day. Some just coming back, others just leaving and yet others that are on the trail and have been for a couple of days. They all have to eat and drink and must have all that in advance. My wife and I parented only had one child, try as we might I guarantee you we didn’t know where he was every minute of every day. So for The Boy Scouts to allow me to help them with their Shooting Sports Training Days is both a flattering and pleasurable experience that I would eagerly accept again.

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Ammunition Accuracy Requirements 101

Written by Sierra Bullets Chief Ballistician Tommy Todd

I load and shoot ammunition for a living. In my duties here at Sierra I constantly test bullet accuracy for our production needs. Because of this, I shoot a variety of different calibers and cartridges on a daily basis and a large demand of this shooting is keeping the guns and loads tuned for optimum accuracy. I have a very narrow window of tolerances to maintain in order to provide our customers (you) with the most accurate bullets on the market.

I have learned many tricks and techniques over the years to tuning a load, prepping brass, and cleaning barrels to keep a gun shooting. I often utilize the things I have learned and take them to extreme levels when competing in a shooting event.  I also often ignore most of these things (other than safety) and simplify the process if the shooting I will be doing does not warrant.

Recently I went on a prairie dog shoot in Wyoming with some good friends. The targets cooperated as did the weather with the exception of some challenging winds we experienced. We had a great time and make a lot of hits on those small rodents. When loading for the 223 Remington rifles and the TC Contender, I cut a few corners in the ammunition loading process due to both time constraints and accuracy needed. When shooting at a prairie dog a miss is simply that, but when shooting at say the X-ring at 1000 yard competition a poorly placed shot is reflected in both your score for that shot and placing in the match. Because of this, I can afford to miss an occasional shot at a varmint due to ammunition capability without worry but will not allow the same tolerances in my match ammo. For the Wyoming trip I utilized a powder measure and simply dumped the charges into primed cases that had been full-length sized and primed.

I had measured enough for length to know that while there was some variance all were under maximum length. I know there is some variation of the measure I utilized but not significant enough to warrant weighing every charge. When seating the bullets a competition seating die was used and I verified OAL on the occasional cartridge to make sure nothing changed.

The ammo produced shot under one inch at 200 yards in one of the guns I planned on taking on to Wyoming with me. I knew I had loaded ammunition that was quite suitable for the task at hand which was evidenced by the number of hits I was able to make at fairly long range.

Today I am loading ammunition for a completely different scenario. This weekend, I will be competing in the The Missouri State F-Class match. This is a six hundred yard match and some extremely good shooters will be in attendance. A person will not be able to lose very many points or they will not place well in the standings after 160 rounds for record. Because of the need for extreme accuracy I have taken equally extreme measures with the ammunition loading. I anneal the brass for this rifle every two firings. I clean the primer pockets every firing, the cases are checked for length and trimmed to exact length every firing. I am weighing every powder charge to the hundredth of a grain, (yes I am weighing to the kernel of powder). Rather than using a standard seating die and a loading press I am using an inline seating die with an arbor press and a gauge that indicates bullet seating pressure, what minor variation is observed in seating pressure is grouped together instead of mixed.

Every round is verified for OAL with an ogive comparator and any variation is culled. The work put into this ammunition serves two purposes. One is that the consistency gives very low extreme spreads which equals to very little vertical variation of the load and very good accuracy. The second product of all this work is the confidence that if I do my part the gun and ammo will shoot extremely good scores.

My point with this is that you must be able to load ammunition that is equal to your need of accuracy. If you are shooting at water balloons at 200 yards your ammunition doesn’t require weighed charges and frequent case annealing, but if extreme accuracy is required if you take shortcuts with your ammo it will show up on target. If you have questions or want more information on loading for extreme accuracy visit our website or call and visit with our technical department – 800-223-8799.

Posted in Hunting Stories, Reloading, Uncategorized | Tagged , , , , , , , | 7 Comments

Super Clean Brass Without Breaking The Bank

Written by Sierra Bullets Ballistic Technician Gary Prisendorf

I recently purchased 1,000 rounds of once fired 5.56 LC brass that was fully processed and ready to load. The brass had been wet tumbled, using stainless steel pins and looked great inside and out, including the primer pockets.

I had always used a vibrating tumbler with either corn cob or walnut media and I always thought my brass looked pretty good until I saw what the wet tumbling and pin combination did.

Being the budget minded reloader that I am, I started looking for a cheap way to wet tumble my brass using stainless steel pins. Harbor Freight had recently opened a store nearby and I had received coupons in the mail, one of the coupons was 20% off any one item.

So I headed for the Harbor Freight store and after roaming around for 20 minutes or so I found a dual drum rotary rock tumbler for $55.00 and thought it would do just fine for what I was planning. The drums are rather small and only have a 3 pound maximum load limit each, but I figured that was big enough for around 150 .223 cases or maybe 300 9MM cases at a time.

I pulled the wrinkled up coupon out of my pocket, paid, and walked out with my new $47.00 brass cleaning machine. I didn’t have any stainless steel pins and couldn’t find any locally.  At our local hardware store I picked up some brass plated ½” finishing brads that I thought might work until I could get some pins ordered.

I bought two small packages of the finishing brads(1.75 oz.), for $1.69 each then headed to my local Walmart to pick up some Dawn dish soap (.99 cents) and a bottle of Lemi Shine ($3.27).  I had read online that is what a lot of people use for cleaning their brass.

When I got home, I started depriming .223 brass for my new toy, I mean brass tumbler. I deprimed 100 cases, put 50 in each drum, dropped a package of brads in each one, filled them ¾ of the way with water, gave each drum a small squirt of Dawn dish soap and a tablespoon of Lemi Shine. I sealed up the drums and fired up the tumbler.

After an hour and a half, I just couldn’t stand it any longer and had to see the results. The water was filthy but the cases were super clean, I couldn’t be happier. For a total investment of around $55.00, I can now get my cases looking almost new.

Here are the before and after pictures of my first run of brass.

I have since ordered two pounds of stainless steel pins, I put one pound in each drum. To be honest the brass really doesn’t look any better, but the pins don’t seem to get stuck inside of the cases near as bad as the brass plated brads did.


Tip: Make sure to inspect your cases and look inside each case to ensure all of the brads/pins are removed.

Just lay the brass and brads/pins out on a towel and let them dry. Mine were dry after about 12 hours.

If you want your cases to look like new without breaking the bank, give it a try. You can’t clean 1000 at a time like the $200.00 tumbling machines that are made for specifically for brass, but this is a much cheaper alternative and the results speak for themselves.

Posted in Reloading | Tagged , , , , , , , | 28 Comments

The M118 LR Chamber: The .223 Wylde of the .308 AR World

Guest blog from our friends at Criterion Barrels, Inc.

A typical AR-10 or other .308 AR pattern rifle will normally come standard with a SAAMI specified .308 Win chamber. While this configuration is designed to accommodate a wide range of different ammunition options effectively, it is less than ideal for a precision .308 AR rifle build. A wider throat diameter (.310) and shorter freebore length (.090) will allow the rifle to accommodate chamber pressures typically found with factory loads, but the wider inside diameter of the throat can cause complications with bullet and bore alignment during feeding, limiting accuracy potential with high performance ammunition.

Criterion Barrels Inc. typically utilizes a .223 Wylde design on their AR-15 barrel models. The benefit to this design involves a slightly tighter throat angle than its 5.56 NATO counterpart, with a longer freebore (when compared to the .223 Remington) to counteract the additional chamber pressure introduced by the modification to the throat design.

 

Applying this principle to the .308 AR rifle platform, Criterion elected to use the .308 Win M118 Tactical (308 M118 LR) chamber as a basis for their reamer design. This configuration offers a slightly thinner throat (.3085 diameter) with a longer .117 freebore to effectively regulate chamber pressure and account for variance in bullet design.

While this chamber design can safely and reliably function with any number of standard factory ammunition options, by slightly modifying the traditional throat dimensions this chamber can very effectively accommodate the ogive of the Sierra 168 HPBT #2200 and 175 gr. HPBT #2275 MatchKing bullets loaded near or at magazine length.

By tailoring their chamber to optimally function with some of the most prevalent match bullets on the market, Criterion Barrels Inc. is able to offer a .308 AR barrel design that offers consistent sub-MOA performance.

Posted in Competitive Shooting | Tagged , , , , , | 3 Comments

Sectional Density, What Value Does it Have Today?

Written by Sierra Bullets Ballistic Technician Paul Box

All of us who have been in reloading and shooting for any period of time have read how sectional density has been regarded as a bullet’s ability to penetrate.  Back before high velocity came along and modern bullet design, the easiest way to get more “power” and penetration was by increasing the diameter and mass. After all, a bowling ball will hurt more than a golf ball, right?

Let’s take a closer look at sectional density.

The formula for calculating sectional density is pretty simple and straight forward.  Take the bullet weight and divide by 7000. This number is then divided by the bullet diameter squared. Two bullets of equal weight and the same diameter will have equal sectional sectional density. No regard is given to the bullet construction. This is where the fly hits the soup in considering sectional density as far as penetration is concerned.

Bullet construction is the biggest factor in how it is able to penetrate. The best example I can think of here is to look at the Sierra .224 55 Gr. FMJBT GameKing #1355 compared to the 55 Gr. BlitzKing #1455. Both are .224 and weigh 55 grs. Both have a sectional density of .157. But there is a huge difference in their construction. The FMJ has a thick jacket and is designed to penetrate. The BlitzKing is designed for fast and rapid expansion with little concern for how deep they will penetrate.


The next time you’re choosing a bullet, look at the construction and less at the sectional density number. It’s all about the construction anyway.  If you have any questions or would like to discuss sectional density or bullet penetration further, please give us a call at 800-223-8799 or shoot us an email at sierra@sierrabullets.com.

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Long Range Load Development

Written by Sierra Bullets Product Development Manager Mark Walker
[First published July 3, 2014]  

Walker1
Since I just put a new barrel on my F-class rifle this spring, I figured it might be a good time to discuss load tuning for long range shooting. Getting the most accuracy out of your rifle is one of the most important aspects of load tuning. For long range shooting in particular, using a load that produces the least amount of vertical variation is vital. There are several steps to the process that I use, so I will go through the basics of each.

When I first get a new barrel installed, I like to determine what the loaded cartridge “jam” length is. I do this by taking an empty case (no powder or primer) that has been neck sized with the proper bushing (I like to shoot for 0.002 smaller than the loaded cartridge neck diameter) and seat a bullet long in it so that the throat of the rifle will move the bullet back into the case when I close the bolt. I close the bolt several times until the bullet stops moving back into the case at which point I use a comparator with my calipers and get a length measurement on the cartridge. This is what I consider to be the “jam length” for this barrel and chamber. I came up with 3.477 as the “jam length” for this particular barrel.

Next, I will fire form some brass using a starting load of powder and bullets seated to “jam” while breaking in the barrel. My barrel break in process is not very technical; it’s mostly just to get the brass formed and the rifle sighted in. I do clean every 5 rounds or so just because I feel like I have to.

Once I have the brass formed, I use them to load for a “ladder “ test to see what powder charge the rifle likes. With a ladder test, you take your starting load and load one round each with a slightly increasing amount of powder until you reach your max load for that cartridge. You then fire each round using the same aiming point to see where the bullets start to form a group. For this barrel and cartridge, I started at 53.3 grains of H4831SC powder and increased the load by 0.3 grains until I reached 55.7 grains. I always seat my bullets to “jam” when doing a ladder test. We will determine the final seating depth in another test later. It’s usually best to shoot this test at a minimum of 200 yards because at closer ranges the bullets will impact too close together making it hard to determine which load works best. I shot this test at 300 yards.

Walker2072 copyAs you can see from the target, the lightest load #1 had the lowest velocity and impacted lowest on the target. Shots #2 and #3 were a little higher and in the same hole. Shots #4 thru #6 were slightly higher yet and all had the same elevation. Shots #7 and #8 were the highest on the target however pressure signs were starting to show. For some reason shot #9 went back into the group and the chronograph didn’t get a reading so I ignored that shot.

When picking a load, I am looking for the most shots at the same vertical location on the target. As you can see that would be shots #4 through #6 so I would pick a powder charge from those shots which would be 54.2 grains to 54.8 grains. As a side note, shots #2 and #3 are only 0.851 lower so I wouldn’t be afraid of using one of those loads either. I settled on 54.5 grains as the load I wanted to use. It’s right in the middle of the group so if the velocity goes up or down slightly, the bullet should still hit in the same place on the target.

Now that we’ve settled on a powder charge, I want to find the seating depth the rifle likes. I usually start at jam length and move the depth in 0.003 until I get to 0.015 deeper than jam.  I load 3 rounds at each depth using the 54.5 grain powder charge and shoot a group with each depth at 150 yards. As you can see from the target, the first two groups are not good at all. Next one looks good and is the smallest group on the target.  The next three are not quite as small but the vertical location on the target is almost the same which indicates a sweet spot which will help keep the vertical stringing to a minimum on target. I went with 3.470 which is right in the middle once again and should give some flexibility with the seating depth.

Walker3074ASo after all of that, my load is 54.5 grains of H4831SC and a cartridge length of 3.470. I plan on loading up enough ammo to shoot five groups of five shots and see exactly how this load works on target as well as what the extreme velocity spreads are over several groups.

I sincerely hope some of this information helps you to get the best accuracy out of your rifle. I do not take credit for coming up with any of this, a whole lot of good shooters use this same method or a variant of it when working up their loads.

For more information about load development, please contact the Sierra Bullets technical support team at 1-800-223-8799 or by email at sierra@sierrabullets.com.

Disclaimer: Load data represented here may not be safe in your rifle.

Posted in Competitive Shooting, Reloading | Tagged , , , | 2 Comments