Cast in M1 Garand - Verical stringing

[dale2242]

I have been playing a H&G # 20 160Gr boolit cast from 50/50 COWW/Lino using 50/50 lube sized .309.
IMR 4064 powder was used. Why? Because I have a lot of it.
I have been using .75-1 gr. dacron.
32 gr shot into 3/4 in. at 50 yds. not counting 1 flyer. These groups each had 8 rnds fed from enbloc clips..
I loaded 33gr, 34gr, and 35gr and had vertical stringing with all loads except the 32 gr. load.
The groups were 3/4-1in. wide with the vertical stringing.
I was thinking these 76 year old eyes were causing the stringing until I shot the 32 gr load. BTW, I shot it last.
All groups were fired with issue sights.
All loads functioned the rifle flawlessly with zero leading.
Chronographing is in order as well as 100 yd. groups.
More to come. Big storm heading to the NW so more testing will have to wait......dale

[TNsailorman]

Interesting, keep us informed on what you find. james

[Adam Helmer]

dale2242,

I have several Garands and my best cast boolit in all is the Lee .312-185-1R sized .309 ahead of a charge of IMR4895. The load cycles all actions and shoots to the sights the same as my 150 grain jacketed loads. I have not seen any verticle stringing in any of my Garands.

If you try IMR4895, perhaps you may end up with my favorite load and no stringing.

Adam

[Outpost75]

I shoot IMR4064 in my Garand. It is a rack-grade CMP gun, not accurized. Springs are new and stiff, so it takes 40 grains to cycle with 160-grain bullet. With 40 grains I don't use any Dacron filler and the groups are round. Typical results with battle sights at 100 and 200 yards:

Attachment 212559Attachment 212560

[Elkins45]

That’s good shooting with a rack grade gun. It must have been rack grade because of cosmetics because it looks like your bore is in good shape.

[Gewehr-Guy]

It surprises me that 32 grs will reliably operate the M1, has anyone ever shortened the op rod springs to allow milder loads to function in their M1's? Would be an interesting experiment.

[mac1911]

It surprises me that 32 grs will reliably operate the M1, has anyone ever shortened the op rod springs to allow milder loads to function in their M1's? Would be an interesting experiment.

I,have not had any decent accuracy with my cast loads through my M1s . one will cycle at 32 grains of H4895 but holds a loose group and its work keeping them in the black.

[TNsailorman]

Control at the gas port is where any changes need to be made. Shuster made an adjustable gas nut for the M1 and M1A to be able to change amount of gas allowed to pass thru the port to the operating rod. Allowing more or less gas to the Op Rod speeds up or slows down the Op Rod and allows gas pressures to be regulated up or down. One of the best ways to use lead bullets at lower velocities is to close the port off completely and operate the rifle like a bolt action. my experience anyway, james

[kaiser]

I did not even consider cast loads in my Garand until I read your post (and others) on the subject. I was concerned about leading, cycling, and "gas plug" fouling, which does not seem to be a problem. I will be interested to hear of the results of the chronograph testing and more loads. Thanks!

[Hick]

You don't have to close off the gas port to operate the M1 as a bolt action-- just open the gas valve wide open and leave it that way (I have two plugs-- one normal and one with the valve removed so that it is wide open).

[Pirate69]

The shooting of cast in a M1 Garand is tough as best. I am still trying to reach the 2.5" groups. See National Match specs below for National Match with jacketed ammo. I guess I am pursuing a dream that may not be possible. But it is fun chasing it. Now looking at glass bedding a stock to see if the groups will tighten. Currently running 3.5" to 4.5" or so. May be as good as it will get. Problem is that I am seeking groups like I see with a good bolt action. Pipe dream????

"National Match M I rifle accuracy standards are as follows. The rifle is tired three 100 shot groups at 100 yds.,
and if practicable match quality ammunition should be used. The average extreme spread of these groups should
not exceed 3.5". Anyone 10-shot group making up this average should not exceed 5.0" extreme spread."

[Earlwb]

One thought is that it may be your heart beat which is causing the vertical stringing. With iron sights you don't see it. But with higher power rifle scopes you can really notice it. But that is some pretty good shooting there with the iron sights though.