Speedy hammers

I was a little worried about the Benchmark, but believe I'm in a decent zone. I swore off making these types of loads for the Creedmoor-ish cartridges. Had a close call with N530, I think it was, or RL 10x - or maybe it was 3031. I was using all those at the time. I generally go the other way and pack the case full of one of the slowest powders I have (which is what I wound up doing for the Creedmoor and similar), but with a Win Mag, I didn't think I could get good results or enough recoil reduction that way. May be a 2nd choice next range session.
X2 on the stuffin em full. Just about everything I seat crunches.
 
52.0 gr Ramshot TAC
 

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358 Winchester Report: 20 rounds total load development/proof. 10 rounds to test pressure, 5 rounds for vel/ES/SD, and 5 for group. Avg vel- 2757 fps magnetospeed. ES- 10, SD- 4. 5 shot group .479" @ 100yds. Keep in mind this aint a "long range rig" with a hubbell telescope on top. This is a hunting rifle with a sporter weight 22" barrel and a 3-9 burris. Loving these Hammers! 😍
 
358 Winchester Report: 20 rounds total load development/proof. 10 rounds to test pressure, 5 rounds for vel/ES/SD, and 5 for group. Avg vel- 2757 fps magnetospeed. ES- 10, SD- 4. 5 shot group .479" @ 100yds. Keep in mind this aint a "long range rig" with a hubbell telescope on top. This is a hunting rifle with a sporter weight 22" barrel and a 3-9 burris. Loving these
 
I was able to put 1 group down range yesterday with the 124 HHs in .300 Win Mag with the 60gr Benchrest load. Velocities had a wide spread (typical of low-density loads) and were quite a bit lower on avg than I anticipated (under 3200) BUT, this was a load I concocted because I wanted a reduced load. I used Rem 9 1/2M primers, and did see slight pressure indicators indicative of a pressure spike (faint ejector marks). The cup/core 130gr Hornady with 65 grains of IMR 4064 also showed the same slight pressure and velocity was the same at a little below 3200 ft/s. I am definitely scrapping the Benchrest load. Group was 2", and this is a brand new Sauer 101, which has the lock ring and pressed in barrel. Not sure if it will handle any of the lightweight bullets. I need under MOA to even consider its use. A regular large rifle primer would have probably given a smaller spread and more consistent results with these faster burning powders, but it met my magnum-primer-criteria of a 60-grain or more volume. I will continue with the other loads as I continue to break in the barrel. Overall, I can get a lightweight 308 Winchester with same 24" barrel and get better velocity with these same bullets using nearly 1/3 less powder and 1/3 less recoil. The Sauer 101 is stocked with the hollow plastic stock, which I filled with foam, and is a very lightweight and handy rifle. However, even with the 60 - 65 grain charge weight and light bullets, the rifle really "comes to see you" upon pulling the trigger (which is a crisp 2 lbs).

Trying the Hammers in the 22 Creedmoor, I was amazed to learn that my average was well below 3000 ft/s with the 73gr (measured 72gr), although the group was excellent at 5/8". I used 40.7 grains of MRP. By contrast, I registered just north of 3050 avg with Barnes 78gr using 39.0 grains of H4955. Group was over 2", just first shot was a cold-bore/clean-bore shot that landed 2" above the center of the last 2 rounds, which were 7/8" apart. Trying to track cold bore shots, because guess what I'll have in the field??! This has bitten me before at longer ranges. I had my first group in the. 22 Creed go into 1/2" with Norma MRP using 40.0 grains with the Barnes 78gr TSX a couple weeks ago. I did not check velocity on that one, so I can't compare apples to apples with the Hammers yet. I have several more good loads made for the Creedmoor, but I am of the opinion that I'm not pushing it to its fullest potential. There is zero pressure and the primers look just like they came out of the sleeve except with an indention. I have room in the case for a little more, but the Hammers have the loads very slightly compressed. It may be worth me breaking out my last remaining supply of AA3100 and Win Supreme 780. I think a slower ball powder would be a great choice here. Superformance might be the bomb, but I rarely get great groups from Superformance in anything. 4000MR is next up on deck...

FWIW, this is a BRAND NEW chronograph, and since both rifles are about 150ft/s slower than I thought they should be with their respective loads, I am going to set up the new chrono with the old chrono in series to verify the new guy knows what he's talking about. My old one was spot on for lots of years, but finally got to where it would start spitting out random numbers and quit altogether after about 40 minutes of use out in the sun. It's still good for several rounds, so I can use it to check the new one. Will report more findings as they are uncovered.
 
H4895 is a good powder to use for reduced loads.
The H4895 is where it's at! This gave best accuracy. I ran 61.0 grains and seated .060" off the lands, but the velocity spread was wider than I wanted. I need to tweak and check velocity on a cloudy day shooting a little higher in the diffuser triangles. I got different reading between the 2 chronograph (both ProChrono), It was bright and sunny and one chrono had diffusers and one didn't. I was only shooting maybe 3" over the sky screens, and distance from muzzle was probably only 7 or 8 feet. I had lots of this vertical stringing going on, even though I was letting the barrel cool to near ambient between shots. It is a thin barrel and it was a solid 90 degrees and climbing when this was shot (yesterday am). German steel is great, but this barrel is thin and may could have used more stress relieving.
 

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Lots of pieces in the system including the chronograph.

Validating all of this stuff has always been hard.
+1. I'd try multiple chronographs under same weather conditions and compare readings....even then there isn't any guarantees but. might be interesting.
 
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