M1 carbine target autopsie

[Old Iron Sights]

Just started working with cast in this newly acquired inland. my first carbine btw. The target below is at 100 yds. It appears to me to be maybe a bedding or harmonics issue. The first few shots I was getting the rear sight adjusted and cleaning the bore. The last six grouped into two very distinct groups. Coincidence or harmonics?
Load is a Lee 311-100 over 11.4 gr 2400.
Match grade professional target board :-)
99113

[35remington]

Given that you're using a plainbase bullet at what will turn out to be a velocity that plainbase bullets often don't do well, I wouldn't make any assumptions about how the rifle is bedded or anything else unless the same symptoms show up with jacketed bullets.

In other words, analysis is futile at this point unless you can positively isolate that your load is correct......and right now, you can't. This may be the best the load can do.

Several more groups please. One proves nothing.

[45 2.1]

I've never been a fan of 2400 in the carbine. I found WW296 was more accurate and consistent in it. A good GC mold helps quite a bit in the accuracy department also. The RCBS mold has been an excellent shooter for me.

[35remington]

Also....since the M1 carbine rarely puts clusters of three close together at 100 yards like your groups imply, what you're seeing is likely as much a fluke as anything. You're "reading into" your target and divining that you may have a sub MOA carbine on your hands.....and likely you do not. Most shoot reasonably, but not as well as you're obviously hoping they do.

[Old Iron Sights]

I'm not going for 1" groups here. I realize the carbine is what it is. I shot 8 rounds last week at 100 yards. 3 cast and 5 aquila factory rounds. All were in the same 4" group. 7 were inside 3". That I'm satisfied with. I took the action out since then. Is there a secret to the tension on the front band? That's all in really looking for at this point. Need to narrow down the variables and shoot more groups.

[badgerblaster]

What I do with my carbine is make sure the receiver is firmly under the recoil plate and screw the recoil plate down so the barrel rides a little high over the stock. Just a couple inches or so. Then pull the barrel down in place with the hand guard and attach the front band as normal.

I'm shooting Lee 120 gr gas checked boolits over 296/H110 at approx. 1800 fps and getting 4 inch groups pretty consistently when I do may part.

[30calflash]

I'm not going for 1" groups here. I realize the carbine is what it is. I shot 8 rounds last week at 100 yards. 3 cast and 5 aquila factory rounds. All were in the same 4" group. 7 were inside 3". That I'm satisfied with. I took the action out since then. Is there a secret to the tension on the front band? That's all in really looking for at this point. Need to narrow down the variables and shoot more groups.

Removal of the action from the stock may be the culprit. Even though everything goes back as it were, sometimes firing 20 or so rounds are what's needed to get it back to pre field stripped status. Happens with other standard grade SA rifles. HTH.