M1 .30 Carbine sucess @ 14gr & 14.8gr

[jedi]

First thank you to all those that have given me advise and suggestions on this caliber. I was finally able to do a full test and have found some settings that this rifle likes.

Rifle: Auto Ordinance M1 Carbine Paratrooper edition
Bullet 1: Berry Platted 110gr
Bullet 2: FMJ 110gr
Powder: WIN 296


Here is the backstory to my journey on reloading for this rifle.
https://www.indianagunowners.com/fo...-30_carbine_sucess_and_question_on_crimp.html
and
https://www.indianagunowners.com/fo...es_higher_velocity_give_better_groupings.html

I loaded the following rounds:
14gr to 14.9gr in increments of 0.1gr for FMJ
14gr to 14.5gr in increments of 0.1gr for Platted

I stopped at 14.5gr because I think that past that the velocity is more than what the platted bullets are rated for. I don't have a way to measure them but per Berry's website it's best to not go over the middle of the road with their bullets. So I stopped there.

Here are the results:

14gr

14.1gr

14.2gr

14.3gr

14.4gr

14.5gr

14.6gr

14.7gr (the rifle does NOT like this one; recoil is very bad)

14.8gr

14.9gr (lots of recoil but noting like 14.7gr)


Here is what I think were the best powder charges for both platted and fmj.

So if I get platted bullets the 14.0gr is the best for this rifle.
Using FMJ 14.8gr followed by 14.6gr is what the rifle likes.

What I found odd is that at the 14.7gr the riffle is very snappy, the recoil feels like it's double and ongoing where as at the 14.8 and 14.9 yes there is recoil but it's manageable and not painful. Don't understand why this would be? Suspect perhaps the barrel is vibrating "off" at the 14.7gr level? No matter I don't plan on using the 14.7gr

I also found out why the rifle is/was shooting high!
I removed the original leaf rear sight and added one of these when I first got it.

This rear sight was used on the non-paratrooper version of the M1 Carbine and can be set to 100, 150, 200 and 300 yards. Well I was shooting at the 25 yard and had it set at to 100 yard. However after the first shot the recoil on the gun pushed the sight to the 150 mark. So last month when shooting I kept shooting high not because of the gun but because the sight was at the 150 after the first trigger pull!

What I had to do after each trigger pull was push the sight back to the 100 mark. Need to find a way to not have it pull bad to the 150 mark. Any ideas?

 

[Broom_jm]

Awesome stuff, Jedi!

Your targets are a textbook example of what most guys see when reloading for rifle cartridges: Your first groups were not so great, with very clear and predictable tightening of the pattern as you approached the MAX charge. Then, you got past the "sweet spot" and groups opened back up a bit. For the jacketed bullets, 14.6 is your ideal load. It is the most accurate, cycles the rounds well and likely has the lowest standard deviation. The tiny increase in velocity you are getting from the 14.8gr loads is not enough to leave the accuracy point of the 14.6gr loads, IMHO.

As for the sight constantly moving, I had the same problem with the Williams aftermarket peep I installed on my M1 carbine. I fixed it by ensuring I had the sight where I wanted it and then applied a tiny bit of loc-tight on the set screw. (If yours is moving every time, I'm going to suggest you haven't tightened the set screw at all?)

 

[jedi]

the set screw??? You talking about the only screw on the unit right? The one where one side is a wheel and the other you can use a flat head on. I never touched those when I installed the sights.

I messed up the 14.6 target by shooting 12 shoots into it as oppose to 6 like the rest and thus I'm not sure I feel it's really that great vs the 14.8.

 

[Broom_jm]

There is almost certainly a set screw of some kind for the elevation adjustment on that sight. It may be a tiny screw on the side of the unit. As for the charge weight, the extra 6 rounds made it into one ragged hole, so I guess I was impressed by that. IME, and from what I saw in the targets, 14.7 and up was opening up again, plus I like to stay middle-of-the-road on semi-auto loads, when the accuracy is there. Keep in mind there is a gas port and timing to consider and the higher you get above the std load (14.5) the more pressure you're creating. For my money, that 14.6gr load would be where I locked in my powder measure.