07-11-2022, 05:23 AM
Haven't shot the ARC in a few months for various reasons. The Grendel's gotten the call for AR Matches since my 105 gr RDF stash ran out and I've had a great load with 123 gr Scenars, plus it's set up is a clone of my PRS Creedmoor) but that stash is thin and word on the street is that accommodating customers other than Ukraine is not on the top of Lapuas to do list these days (especially with powder for all you VV fans). So back to the drawing board. The 95 gr VLD Targets always seem to be in stock somewhere (including the shelf at Bruno's 15 minutes away), so.....
16" Lilia with MLGS
Base sized 4x never annealed nickel Starline Grendel brass with pockets that accept a no go gauge
Varget from a Chargemaster 1500 dropped through a 5" drop tube
GM 205M
COAL 2.25" / BTO 1.675" (a little under a 0.02" jump)
4 shot strings with the first being one shot through a cold bore. I cleaned it before the last match I used it I but didn't afterwards. Probably 75 rounds at the match. I didn't want to clean in it before this test since a barrel is always a tad fast after cleaning. 92 degrees. 10 minute break between 27.6 and 27.8 (cold range).
Charge / Velocity / SD / ES
27.2 / 2552
27.4 / 2570 / 3 / 7
27.6 / 2588/ 5 / 13
27.8 / 2606 / 7 / 17
28.0 / 2624 / 4 / 11
Shot with magnetospeed on the 0.75" contour barrel. I was stringing vertically likely due to the fact that almost all of my shooting has been with a MBA 1 with the adjustable LOP the last few months and I wasn't getting my shoulder into the carbine stock consistently. Plus, it was on a smooth concrete bench which inhibits getting load into the bipod consistently. And it was at 10x - most of my paper shooting has been through an XTR3 at 30x recently. Nonetheless, the vertical was never worse than 1". The worst horizontal dispersion was 0.5" and the best was 0.15" ( the last, which could partially be attributed to getting more comfortable on the stock). No pressure signs or timing induced markings on brass.
I'm inclined to follow up at 27.4 to keep it milder for the brass and since another 50-60 fps doesn't really get much. Flatter than the 105 RDFs at 2440 with Varget and virtually negligible additional winddrift at 700 yards. Felt recoil was also noticable less at 27.4 vs. 28.0 (and vs. the 105s, which is a big plus with a 7 lb rifle). But I'll probably play around at 28.0 too.
Looking at the numbers, something struck me as practically impossible and certainly not repeatable, but gives me great confidence in the combo. I wonder if anyone else can pick it up......
16" Lilia with MLGS
Base sized 4x never annealed nickel Starline Grendel brass with pockets that accept a no go gauge
Varget from a Chargemaster 1500 dropped through a 5" drop tube
GM 205M
COAL 2.25" / BTO 1.675" (a little under a 0.02" jump)
4 shot strings with the first being one shot through a cold bore. I cleaned it before the last match I used it I but didn't afterwards. Probably 75 rounds at the match. I didn't want to clean in it before this test since a barrel is always a tad fast after cleaning. 92 degrees. 10 minute break between 27.6 and 27.8 (cold range).
Charge / Velocity / SD / ES
27.2 / 2552
27.4 / 2570 / 3 / 7
27.6 / 2588/ 5 / 13
27.8 / 2606 / 7 / 17
28.0 / 2624 / 4 / 11
Shot with magnetospeed on the 0.75" contour barrel. I was stringing vertically likely due to the fact that almost all of my shooting has been with a MBA 1 with the adjustable LOP the last few months and I wasn't getting my shoulder into the carbine stock consistently. Plus, it was on a smooth concrete bench which inhibits getting load into the bipod consistently. And it was at 10x - most of my paper shooting has been through an XTR3 at 30x recently. Nonetheless, the vertical was never worse than 1". The worst horizontal dispersion was 0.5" and the best was 0.15" ( the last, which could partially be attributed to getting more comfortable on the stock). No pressure signs or timing induced markings on brass.
I'm inclined to follow up at 27.4 to keep it milder for the brass and since another 50-60 fps doesn't really get much. Flatter than the 105 RDFs at 2440 with Varget and virtually negligible additional winddrift at 700 yards. Felt recoil was also noticable less at 27.4 vs. 28.0 (and vs. the 105s, which is a big plus with a 7 lb rifle). But I'll probably play around at 28.0 too.
Looking at the numbers, something struck me as practically impossible and certainly not repeatable, but gives me great confidence in the combo. I wonder if anyone else can pick it up......
#FJB