That's TO much pressure with Unique!

10.0 gr would be ok.

A loose primer is a sign of excessive pressure.

There are no silly (stupid) questions asked here. You'll find a wealth of information and a sincere willingness to help you.

Unique is very useful with light bullets around 1100 FPS in the 38/55. All my Unique 38/55 loads are fixed cartridges subsonic due indoor range requirements. 

Heavier bullets 300 + my best powder was 4759 now discontinued, later switched to 4227. It’s ideal for 200 -300 yards accurate to 500, larger bore probably better for over 300 but the 38/55 has its advantages at long range. Mild recoil one.

Those powder's suit my shooting mostly due to holding velocities to about 1250 outdoors longer ranges. Something else could be better higher velocity 

Boats 

Thank you!
I appreciate all your input!

Do you guys start with a mild charge and work your way up watching velocity with a specific velocity in mind?
I’ve read some threads here on the forum about having velocity supersonic all the way to the target, that’s why I was trying to get up to 1350 fps. That was just a guess of how fast I would need to keep it supersonic out to 100 yards 
This may have been a false assumption on my part also

Thank you again 

Jason

I’ve always loaded my CPA 38/55 with smokeless to black powder velocity’s. Reason is BP required in matches, wanted practice smokeless loads to nearly same sight settings. Never saw a reason to go faster. They are supersonic for a bit then settle down to sub sonic before 200 yard targets. I consider it a good combination to 500 yards.  It won’t knock over all rams but in my hands  shot higher scores than bigger calibers, = hit more targets.

32/40 other hand works well with smokeless at about 1450 fps. It’s just supersonic at 200 yards with charges around  14.5 grs of 4227. Some days some rifle ranges (not all are measured accurately)  need a bit more powder. You can see the wiggle holes on paper if they go subsonic at point of impact. 

Others may see it different.

Boats

Back during the development of what eventually became the 338 Lapua, the original Brass was produced by Bell for the RAI Model 300 rifle in the early 1980's. It was known to be soft and often it was impossible to open the bolt without the aid of a plastic mallet. I was told (ca 1988) a contributing factor was that the bullets used were 0.339 and were also spiking pressures causing the tie-ups. I ended up with some of this brass and used it in my Rem 700 based 8.58x71 (military designation before 338 Lapua). You can see where the base of the casing was extruded into the ejector pin hole of the bolt face using the loads recommended to me by the gunsmith at RAI, he barreled and chambered my 700.

Anyway, primers were not falling out until I have loaded the cases more than 5 times 

BTW: note the lack of the headstamp...