mjcmichigan
Handloader
- Dec 26, 2016
- 2,432
- 407
So my Marlin 336 XLR ( remlin micro groove)
Has shot no better than 1.25” at 100 yards.
I find that satisfactory, but it was difficult to get there. I think I might have found the issue/irregularity… I got the Hornady kit to measure neck thickness and I found a lot of my brass has an abrupt bump. The brass I necksized with a Lee neck sizer (undersized by 0.0005”) is pretty consistent at 120-135/10,000th (so 0.012-0.135”). The other brass will range 0.012-0.015, and on the ridge jump to 0.020…. So 6-8/1000ths thicker. To me, this seems like a potential source of inconsistencies.
To try to remediate this brass, I think I will 1) anneal it, 2) neck size with the undersize rod.
3) trim it, 4) turn the necks…
I didn’t mention it is starline brass.
I inherited a bunch of R&P brass… I had horrible concentricity…. RCBS seater.
Got some Redding dies, that helped concentricities. Still was having issues and made a good batch with some FC nickel brass. Upon examination, neck wall was running 0.011-0.015. That is the brass that was giving a decent group. I don’t recall SD, but it was single digits.
All this to say, asking if anyone thinks I should try something else…(ie throw the brass out and start over with a new batch)
Has shot no better than 1.25” at 100 yards.
I find that satisfactory, but it was difficult to get there. I think I might have found the issue/irregularity… I got the Hornady kit to measure neck thickness and I found a lot of my brass has an abrupt bump. The brass I necksized with a Lee neck sizer (undersized by 0.0005”) is pretty consistent at 120-135/10,000th (so 0.012-0.135”). The other brass will range 0.012-0.015, and on the ridge jump to 0.020…. So 6-8/1000ths thicker. To me, this seems like a potential source of inconsistencies.
To try to remediate this brass, I think I will 1) anneal it, 2) neck size with the undersize rod.
3) trim it, 4) turn the necks…
I didn’t mention it is starline brass.
I inherited a bunch of R&P brass… I had horrible concentricity…. RCBS seater.
Got some Redding dies, that helped concentricities. Still was having issues and made a good batch with some FC nickel brass. Upon examination, neck wall was running 0.011-0.015. That is the brass that was giving a decent group. I don’t recall SD, but it was single digits.
All this to say, asking if anyone thinks I should try something else…(ie throw the brass out and start over with a new batch)
