50 to 100 accuracy

[abunaitoo]

M1 carbine, group buy mould, 120gr, size to 313di, flat base, Lar45 carnuba lube, 9.0/2400, small rifle primers. Bore sluggs at 310di. Cycles fine.
At 50yds 2"-3", sometimes 1"-2".
At 100yds "5-6" sometimes more.
Comdom 110gr much better.
What is the thinking on powder charge for accuracy???
Would more, or less powder help the 100yd groups?????
Would small pistol primers help????
Different powder suggestions?????

[runfiverun]

bump up the 2400.

[Buckshot]

...............Part of your 100 yard dispersal is going to be the simple fact that it IS twice the distance. Add in the fact that you have a somewhat short sight radius, which increasing ranges accentuates.

"Bore sluggs at 310di." I think you mean groove? You're sizing to .313", to fit the throat? Look to the load also. What kind of statistics are you getting, primarily what do your extreme spreads look like? As an experiment try sizing to .310". What is your case prep before seating the slug? The carbine case is a sturdy rascal for it's size, and if sizing to .313" really IS the answer for accuracy, once your boolit is seated it might be losing a couple thousandths.

What does the 100 yard group look like? Simply all over the place, or is there some pattern to it? You can also attempt to make your cast loads as close to the jacketed rounds as possible. As an experiment weigh some cases and find 20 that are within a half grain in weight. Also scale some boolits and try to keep them within 0.2 gr of each other. Fire 10 at 50 yards and then the other 10 at 100 yards. See if this tightens things up.

...............Buckshot

[Echo]

+1 on bumping up the 2400. I believe I use 12 grains - don't have the data in front of me, though.

[Bret4207]

I use more 2400 than that in my 32-20's, a slightly smaller case. As they said, up the powder a bit.

[1Shirt]

What Buckshot says! It has always been my contention that the 30 carbine in not very effective or accurate beyond 50 yds (in the hands of the average shooter). If it stays consistantly under 3" at 50, I would probably be happy with it. Short sight rad is also a factor, and a well blackened front sight might help squeeze a little smaller group. The best one that I have ever seen with cast would stay around 2" at 50 yds consistantly with well crafted loads, and ALL components weighed. The last is something that I doubt very many carbine shooters do. Good luck!
1Shirt!:coffee:

[abunaitoo]

The barrel is worn out. I'll slugg it again, but the rifling is really shallow.
Sizing my bullets 313 to 314 so I'm thinking it should be good.
I'll try going up in powder, but I'm wondering if the shallow rifling will hold the bullet.
All I can do is try it.
The 100yd groups are all over the paper.

[45 2.1]

Water drop the boolits and use WW296 for the powder. Don't ask the charge as its a little over what some books list.

[Gee_Wizz01]

What Buckshot says! It has always been my contention that the 30 carbine in not very effective or accurate beyond 50 yds (in the hands of the average shooter). If it stays consistantly under 3" at 50, I would probably be happy with it. Short sight rad is also a factor, and a well blackened front sight might help squeeze a little smaller group. The best one that I have ever seen with cast would stay around 2" at 50 yds consistantly with well crafted loads, and ALL components weighed. The last is something that I doubt very many carbine shooters do. Good luck!
1Shirt!:coffee:

Your experience mirrors mine very closely 1Shirt. I worked with a couple of carbines with cast loads and 2" groups was about the best I could ever shoot consistently. I always thought 2 to 3" at 50yds was about the best one could expect from an M1 Carbine. I achieved my most accurate loads with Unique and the Lee 120 gr with Hornady gas checks. These loads were just as accurate as any jacketed loads in my carbine. I also tried bedding one of the carbines and tightening the action in the stock, which did not do a lot to improve accuracy. I finally figured this was as good as it gets and loaded up several hundred rounds and moved on to another rifle project.


G

[Larry Gibson]

Never got much better accuacy than that with any PB bullet in any M1 Carbine (I've shot lot's of them over the years). With a GC'd cast bulletof 100-120 gr Ive not had too much of a problem getting 2-3 MOA groups at 100 yards. Bores must be good, bullets must be .001-.002 over groove depth (not much throat to worry about), alloy must be correct and 4227, 2400 or H110/296 should be used. Never considered weighing .30 Carbine cases, just sort by headstamp. Action and barrel must also be bedded properly, again not hard to do or corect. Not really that hard to get useable accuracy out of them.

Only useable accuracy with PB cast bullets was with 4227 and velocities not over 1500 fps.

Larry Gibson

[Leftoverdj]

I'm with Larry, but on the basis of a lot less experience with the M-1 Carbine. I've used the older plain base Lyman 311410 in a couple, and it was very iffie getting the rifles to function before all semblance of accuracy vanished. In the unlikely event that I ever try it again, it will be with GC bullets.