Signs of high pressure(?) Marlin 1893 38-55 Smokeless Steel Barrel

[WBH]

In working up new loads for my 1893 Marlin 38-55 I noticed a slight flattening of the primers which shouldnt be according to load data.

Here's the specs....

Lee cast 250gr Boolit wheelweights sized .379" seated at the lands
Starline Brass 2.125"
CCI 200 Primers
20.0gr XMP 5744

Should be a low pressure load.....right???

Thoughts

BTW 18.0gr IMR 4198, and 16.0gr SR4759 gave the best accuracy with no visable pressure signs.

[Shawlerbrook]

Could be other reasons for slight primer flattening. Any sticky extraction after firing ?

http://www.massreloading.com/reading_pressure_signs.html

[WBH]

Only sign is slight flattening. No cratering, hard extraction or any other HP signs. By all books and my 50+ years of reloading it just seems strange.

I wish I has 25# of SR4759 left instead of just a little over 1#.

[earlmck]

Yes your 5744 load is a low pressure load. But your other loads are very low pressure loads. So no surprise there is some difference in primer appearance between very low pressure loads and low pressure loads. Keep on shootin'!

[RickinTN]

Your flattened primers are from some other cause. A little excess headspace will give the same signs. If you run into "real" pressure signs in a lever rifle you're way over the design limits of the rifle.
Good Luck,
Rick

[M-Tecs]

Your flattened primers are from some other cause. A little excess headspace will give the same signs. If you run into "real" pressure signs in a lever rifle you're way over the design limits of the rifle.
Good Luck,
Rick

Yep...…...saved me typing this /\/\/\/\/\

[WBH]

Headspace.....Good thought! I have another Marlin '93 that I will try the same loads and see if the flattening is duplicated. Though, being both over 110 years old, they both can have minor headspace issues. Ill run my standard shim tests and see what's up. Thanks.