Yet Another M1S Upper Report

[Flewis]

Thanks for the info guys. On the pierced primers, I had no problem using the CCI-41s. I will check the firing pin length and compare other specs to the bolt in my .223 AR which I've had no trouble with using the WSR primers.

I did notice that the ballistics are pretty much identical to the CCI Standard Velocity (sub-sonic) .22 LR that I shoot a lot of. Now that I think about it, they should be the same other than a slight adjustment for the difference in drag between the .22 and .308 bullets.

I'm loading up another 50 rounds and going back out in a few days to dial it in at 100 and 200 yards. This time using new .223 brass to form the cases and AA1680 powder.

I have a box of .221 Fireball brass that I've formed a few cases from. Many of them look like the neck isn't exactly centered on the cartridge body, which I've read can be a problem when necking up the .221 brass. I hand picked the best looking ones and have used them in my load/velocity testing. If I use the rest of those .221 cases to make .300 Whisper brass, should I expect to see a degradation in accuracy? Just wondering if I should bother necking the rest of those up...

[Pitt300]

I too have a mildot scope w/target turrets.
I've found it easiest when I switch to subsonic loads to simply crank in about 13-14" of UP elevation & then hold dead on the target @ 100 yards.
This is NOT the problem.
The problem comes into estimating 140/150/160 yards as the drop gets severe.
A 200 yard range finder would be ideal!
If you know the distance, it's very easy to dial in elevation & wind drift is minimal w/220 & 240g subsonics.
I use H-110 & VV N-110 w/all loads & everything cycles fine w/M1S upper & A2 stock w/A2 spring & CAR buffer.