O.A.L variation - danger?

[africa]

Seems a rather basic question, but I don´t have an answer...
I'm working .357 mag. loads for a Puma carbine, using 180 gr truncated cone bullets (cast, of course) plus 15 gr. of H110. and getting very good accuracy without any signs of undue hi pressures, but the OAL of the cartrige is 1.56", and a Lyman manual says 1.585" is the minimal OAL for such a 180 gr. bullet load. The carbine will not feed cartriges longer than 1.565".
A less optimistical soul I know swears that the Puma is going to turn my already wrinkled face uglier when the little carbine blows up because of pressure increase due to the shorter pill. Do you think such a small difference - 0.015" will make a difference, since Paco Kelly concotes a similar load with 16 gr. of H110?

[Dale53]

Pressure testing is the only sure way to tell. However, I doubt that .015" will make much of a difference. Keep in mind, that the overall length is not the problem but the difference in seating depth. Some bullet designs may be longer overall but show LESS seating depth.

Just a thought...

Dale53

[StarMetal]

You can't go by what someone else got either. No two guns are alike. I had an early Puma in 357 and was loading a stiff load of 2400 and a 150 gr cast. Shot wonderful in my rifle. Then my friend bought the same model rifle at about the same time period. He tried my load and it was blowing primers for him. Go figure. Same rifles made of the same machinery...but yet different.

If you show no signs of pressure and the cases extract easy it's probably ok. If you don't need the load you're using, you could drop down 1/2 gr or so and feel even more comfortable.

Joe

[Bass Ackward]

Seems a rather basic question, but I don´t have an answer...
I'm working .357 mag. loads for a Puma carbine, using 180 gr truncated cone bullets (cast, of course) plus 15 gr. of H110. and getting very good accuracy without any signs of undue hi pressures, but the OAL of the cartrige is 1.56", and a Lyman manual says 1.585" is the minimal OAL for such a 180 gr. bullet load. The carbine will not feed cartriges longer than 1.565".
A less optimistical soul I know swears that the Puma is going to turn my already wrinkled face uglier when the little carbine blows up because of pressure increase due to the shorter pill. Do you think such a small difference - 0.015" will make a difference, since Paco Kelly concotes a similar load with 16 gr. of H110?


Africa,

Seating depth does make a difference because it makes a difference in volume. The way around that is to start low and work up which is why that saying came about.

[Bent Ramrod]

Africa,

The warnings about shortening OALs typically revolve around loads (especially pistol loads with fast powders) which are already at the maximum pressures and then for some reason the bullet is seated deeper by inadvertent adjustment of the stem or thrust deeper into the case by the action of the gun. If you have developed your loads at this seating depth and the pressure signs aren't extreme, it should be all right.

[lovedogs]

Previous posts were correct. If you were loading too hot due to deep seating you'd already have discovered it. Sometimes it's quite surprising how guns vary in this sort of thing.