Anyone have a SR4756 M1 Carbine load?

[Paul5388]

OCD,

Yes, it's due to the burning rate and pressure it developes at that density of a load.

Since you aren't using a Ruger, it's probably still a good load for your carbine. If primers are a concern, just use a small rifle primer. Whatever you do, don't load more than a couple of test rounds and make sure you weigh the individual charges.

 

[Bruce51]

Originally posted by OCD1:

Originally posted by Bruce Lee M:
OCD1 I think you are risking blown primers and stuck cases.I only fired two rounds and I knew they were over the top. If they were to stick in the carbine you might tear a case head off.
If I wanted to use Unique I would start at 6.5 grains and work up to less than 7.5. You will no longer find this load listed in the books. They now stick to 5.5grs. BTW the 8.5gr BD load does function the carbine perfectly. In a carbine it is supposed to give 1620fps. Any load which exceeds 1500fps will most likely cycle the gun. Bruce

It's not that a really want to use Unique, just that I saw it in the load data and figured i could use half as much powder. Without knowing the pressures I do not understand how the Unique can be a "Hotter" load than what I have been using the H110 and 2400 magnum powders??

Hotter may be the wrong word to describe what is actually happening. The powder is producing higher pressure at that load density. The .30 carbine operates at a maximum of 40,000CUP. If I fire a load which shows signs of pressure greater than a factory load then I have exceeded that pressure. The Unique load of 7.5grs is one of those loads and is the only load that has done so. I all my loads for the .30carbine I use CCI or Federal small rifle primers. The CCI are magnums for the ball powder and the Federals are standard. I am making a very honest effort to prevent you from having a kaboom. My Blackhawk has very generous chambers. No other load has ever stuck in the cylinder or had a primer so flat there was no dimple left in the middle. I had 18 rounds loaded for testing. Two were fired, the other sixteen were brought back and undone. One should always start with a ten percent reduction and work up. Sometimes we need to be reminded of that rather good advice. Bruce

 

[Rule3]

Yes and good advice it is. I appreciate it.I have ben using 14 grs of H110 with 110grJRN CCI small rifle non magnum primer. yields 32,000 cup by the load data 2000fps

 

[Paul5388]

If I fire a load which shows signs of pressure greater than a factory load then I have exceeded that pressure.

It's highly unusual for a 40,000 cup or psi load to show any signs of pressure, especially with a small rifle primer. Small rifle primers are frequently used for rifles in the 50,000 psi range, without any signs of high pressure. The .30 Carbine operates at 40,000 psi, not cup (psi and cup are very close to being the same in this range).

I shoot what is probably 45,000 cup loads frequently in .357 Mag and get less signs of pressure than some highly touted loading manual loads that are supposed to be less than 35,000 psi.

As I said,

If it was mine, I would try Unique, but I'd start low and work it up. However, that's a matter for you to decide.

 

[Rule3]

Originally posted by Paul5388:

If I fire a load which shows signs of pressure greater than a factory load then I have exceeded that pressure.

It's highly unusual for a 40,000 cup or psi load to show any signs of pressure, especially with a small rifle primer. Small rifle primers are frequently used for rifles in the 50,000 psi range, without any signs of high pressure. The .30 Carbine operates at 40,000 psi, not cup (psi and cup are very close to being the same in this range).

I shoot what is probably 45,000 cup loads frequently in .357 Mag and get less signs of pressure than some highly touted loading manual loads that are supposed to be less than 35,000 psi.

As I said,

If it was mine, I would try Unique, but I'd start low and work it up. However, that's a matter for you to decide.

Paul, It's funny you mention the 357. Last night I was looking through my manual and found what I think is a close comparison. I am probably wrong but here it is.

The 357 has useful case capacity of 1.15cc and is 1.290 long.
The 30carbine has case capacity of 1.00 cc and is the same length.

A 357 load is listed for the same weight bullet of 110 gr jacketed using 9 grs low of Unique up to 10 grs max.

Soooo can one "interpolate" from this that the 6.5gr load in the carbine would seem to be safe?
As you said it probably is but kust wondered if this reenforces that or is my "logic" flawed?

 

[Paul5388]

OCD,

As far as I'm concerned, interpolation is an easy way to get into trouble. It's true that the two cases are similar, but they aren't exactly the same. Not only that, but there's also the difference in bearing surface between the two different calibers, even though they weigh the same.

Speer #8 does not list Unique for the Carbine loads. I don't know why they didn't, but since they didn't, it would be best to use the loads they do list. It appears that they have only used the slower powders for that time period.

Max/Min loads for the powders still in production are:
15.5/13.5 gr of H4227
15.0/13.0 gr of 2400
15.5/12.5 gr of H110
11.0/9.0 gr of Herco
all with 110 gr RN and standard CCI 400 primer.

 

[38-44HD45]

My opinion: If you're gonna shoot it in a carbine, 296/H110 is the way to go.

 

[Rule3]

Originally posted by 38-44HD45:
My opinion: If you're gonna shoot it in a carbine, 296/H110 is the way to go.

Yes, that't what I have been using and the 2400. When I saw that 6.5 gr of Unique Just trying to be frugal, you know cheap

I'll stick with the published loads. Thanks