Originally Posted by
Backcut
Greetings! Thanks in advance for any advice, or if you can point me to any stickies that'd be helpful. There are many.
I had a very poor first outing in .308 and 30-30 using precast lead boolits, abysmal accuracy. Could use help diagnosing my errors.
Background:
I previously had decent success with reduced loads in .308 win and 30-30 using Speer 100gr half-J and 110gr TMJ 30 carbine bullets, with reduced 4895 loads, Trail Boss, and 2400. Got around 1.5" groups from the bench at 50 yards, good enough for plinking. Next I wanted to try cast. I have never shot any cast boolits before in handguns or anything else.
I got some .309 precast boolits from Rim Rock, which I believe to be good quality. My poor performance is no reflection on these nice boolits.
For all loads, I used a Lee universal case expander before seating, then crimped with a Lee FCD.
I measured the boolits at .309. The boolits are advertised as coming with magma lube.
I pulled them out of the box and seated them over powder, crimped, and shot. 5-shot groups.
Winchester 94, 1980s manufacture, shot very little.
FC brass, CCI 200 primers
Rim Rock 165gr hard cast RNFP. Advertised 22 BHN, magma lube.
Seated to crimping groove, moderate crimp with Lee FCD.
Powder: 2400
15gr 1650fps 8fps sd
17gr 1769fps 16fps sd
19gr 1919fps 20fps sd
Ruger American 308 Win
PPU brass, CCI 200 primers
Rim Rock 115gr hard cast RN. Advertised 22 BHN, magma lube.
Seated to OAL 2.450", moderate crimp with Lee FCD.
Powder: 2400
16gr 1725fps 20fps sd
18gr 1867fps 6fps sd
Powder: Unique
12gr 1801fps 11fps sd
14gr 1971fps 8fps sd
16gr 2137fps 7fps sd
I shot all of these from the bench at 50 yds, in 5-shot groups. The chrono results were consistent and I was happy with the velocity sd, but accuracy was abysmal. I was all over multiple sheets of printer paper with shots a foot apart at times. Accuracy was bad from the start, it didn't get any better or worse as I went.
After shooting my cast loads, I did 4-5 shot groups of factory Rem 150 in the 30-30 and surplus 147 in the 308, and got close to 1" groups, just to confirm nothing else is wrong.
I think I'm going to set aside the 308 for now, and focus on seeing if I can get the 30-30 to shoot these cast boolits.
I'm not sure how to tell if I'm getting excessive leading, most of the threads I've found on that talk alot about forcing cones. Peering down the barrel I don't see anything that jumps out.
Do I need to slug my barrel(s)? I figured these are relatively new rifles, fired little, with no microgroove or any other funny stuff, and the basic off-the-shelf precast ought to shoot ok at .309 or they wouldn't sell many. These rifles both shoot just fine with my handloads with speer/hornady/whatever .308 projectiles.
Am I at the wrong velocity for my BHN? Manufacturer's FAQ says you can run the 22BHN boolits up to 2200 fps, and I never exceeded that.
I'm thinking there ought to be a way to get the boolits I've got to shoot acceptably well or at least better than this in my 30-30. What should I try next?
Many thanks,
Backcut