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Posted: 8/14/2010 6:46:36 PM EDT
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INTRO:
Today I tested my first hand-loaded rifle rounds. I started by following the recipe (to follow) for the 60gr. .223 Remington load out of the 49th Edition of the Lyman Reloading Manual, then altered the load to experiment with my rifle. My intention was to build a load for Cora (a rifle to be described later) than typical factory 55gr. loads available. EQUIPMENT AND RECIPE: Loaded on a Redding single stage press with Lyman .223 dies -Factory new .223 Remington brass made by Black Hills -Sierra 60gr. Hollowpoint bullets -CCI #400 primers -IMR 4895 powder The original recipe out of the Lyman manual called for 22.9gr. of IMR 4895 loaded into a 1.75" casing and an overall lenth of 2.260". I loaded ten rounds of this to test. I then loaded four more sets of ten rounds, adding .2gr of powder to each subsequent set, which gave me 50 rounds of .223 Rem ammunition with five different powder charges: -10x 22.9gr -10x 23.1gr -10x 23.3gr -10x 23.5gr -10x 23.7gr About every third round was measured for COAL to ensure uniformity after pressing. Because factory new brass was used, brass was measured, trimmed if necessary, and then primed and loaded. No other case preparation was deemed necessary or undertaken. TESTING: All shots were fired from Cora, a 16" AR-15 build with carbine length gas system, 1:9" twist Stag Arms barrel and H2 buffer. A 2.5x BSA scope on Leupold QD rings, zeroed to 25 yards with Herters 55gr. steel-cased ammunition, was used for test firing. Cora was mounted on a GripPod Systems GPS-2 No change was made to the zero for the sake of consistency. Shots were fired at a target positioned at 50 yards from the bench. The target was a piece of 14x17" drawing paper with a 3" Birchwood Casey Shoot'n'See target pasted at its center. Shots were fired at a rifleman's cadence (one shot per slow breath, fired on the out). RESULTS: All shots were well off from the original zero, but all were on paper and high to the 11-12:00. Groups were measured with a Lyman caliper, center-to-center from the outer-most shots. Weather: 78 degrees F, mostly sunny with light wind to the south. Load 1 (22.9gr powder): First shot of the day was a called flier (jerked trigger to the 10:00). The 9-shot composite group was measured. Extreme vertical spread was .977". Extreme horizontal spread was .488". Point-of-impact was 3.739" from point-of-aim to the 11:30. Load 2 (23.1gr. powder): 10-shot composite. Extreme vertical spread was .791". Extreme horizontal spread was .491". POI was 2.975" from POA to the 11:00. Load 3 (23.3gr. powder): 10-shot composite. Extreme vertical spread was .704". Extreme horizontal spread was .771". POI was 3.286" from POA to the 11:30. Load 4 (23.5gr. powder): 10-shot composite. Extreme vertical spread was 1.047". Extreme horizontal spread was also 1.047". POI was 3.238" from POA to the 12:00. Load 5 (23.7gr. powder): 10-shot composite. Extreme vertical spread was .681". Extreme horizontal spread was 1.100". POI was 2.90" from POA to the 11:30. CONCLUSIONS: All groups were similar, and most variance was likely mistakes on the part of the shooter (a.k.a. me). By taking the larger of the extreme spreads of each group, Load 3 produced the tightest group. By taking the smaller of the extreme spreads, the Load 1 produced the tightest group, but one shot was excluded. I will try Loads 1, 2, and 3 again for further testing. Your thoughts and comments are appreciated. |
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Doesn't sound too bad so far, It is hard to double charge a rifle case but easy to do on the pistol. Once you get in the ballpark of what load your rifle likes then you can start to fine tune the charge weight.
Also keep in mind that every rifle may like a different load. |
| It has been brought to my attention by a friend that it really is too soon to settle on a specific load, as 10 rounds isn't enough for a good evaluation. I will be repeating all of these loads and use what he called the "ladder method" to try to figure out what my rifle likes. Will probably add a few more to the test, following the same +.2gr of powder pattern as well. |
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The normal method of measuring groups is to measure center to center the two farthest holes. Hard to follow with Hor. and Vert. spread.
Installing a bullet is called seating not pressing. Don't worry about not knowing all the terms yet, your method of working up is sound. What I do is work up in .4 steps until I get to 1 gr below max listed, then go to .2 steps. Once I think I have a load I like, I shoot several groups looking for consistency. Good luck |
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Couple things come to mind. Starting low and working up is great, but I think you are using rather small increments, I would increase by .4 or .5 until I got up around 24-24.5gr then drop to .2 or .3gr and continue on to max.
I do all my load development at 100 yards then go out farther. Never found much difference in loads at 50 yards. Because factory new brass was used, brass was measured, trimmed if necessary, and then primed and loaded. No other case preparation was deemed necessary or undertaken.
This has been debated several times, but IMO sizing new brass is a must, at least use a neck die to straighten out what shipping and handling has buggered up. Even if you don't size your new brass you should always chamfer and de-burr the case mouth. |
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Thanks for the advice! I was playing around and testing out my equipment with this, just getting a feel for everything. As I keep loading, I'm sure I'll get the terms and techniques down a bit better. Again, I'm new at this, and was playing it safe with my conservative powder increments.
As to the comment about 50 vs 100 yards, my optic is a piece of crap and I couldn't really see well enough at 100 yards to get a good sight picture (my crosshair is too thick) on the target that I had. I'll try with an actual zeroing target and a rest next time. Also, I deburred and chamferred all cases prior to seating*. *That does sound better. Cheers! |
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I would second the "ladder" method; it is a sweet method that I tried recently with success. The only thing is that method is usually best done at least at 200-300 yards range since it requires a bit more spread for you to evaluate the hits and ID the sweet spots, unfortunately the OP is having problems at 100 yards..... You need to get a better scope. For those unfamiliar with this method, I got the URL from this board, it is at:
http://www.desertsharpshooters.com/manuals/incredload.pdf The other thing I would suggest to the OP is to not judge the grouping by eye but to use the fantastic and free “OnTarget” software developed by Jeffrey Block. You can download it here: http://www.6mmbr.com/ontargetsoftware.htm |
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Quoted:
I would second the "ladder" method; it is a sweet method that I tried recently with success. The only thing is that method is usually best done at least at 200-300 yards range since it requires a bit more spread for you to evaluate the hits and ID the sweet spots, unfortunately the OP is having problems at 100 yards..... You need to get a better scope. For those unfamiliar with this method, I got the URL from this board, it is at: http://www.desertsharpshooters.com/manuals/incredload.pdf The other thing I would suggest to the OP is to not judge the grouping by eye but to use the fantastic and free “OnTarget” software developed by Jeffrey Block. You can download it here: http://www.6mmbr.com/ontargetsoftware.htm Yeah, a better optic is in the near future. This one was originally bought to allow me to zero my irons for M193, and still have a way to shoot my .22 conversion accurately. Thanks for the links! |
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