[mcj600]

Finally, after 2+ years of scraping up the time & $$$, I finished my build!!!
THANKS TO EVERYONE THAT ANSWERED MY MULTITUDES OF QUESTIONS ALONG THE WAY! It was an interesting journey - the highlight was the night I started drilling my 80% RSP; the wife went into labor with our first Reluctantly, I had to stop work and rush to the hospital
Anyway, I took my 1919 out for the maiden voyage last weekend and had the usual learning curve issues but it was working well after an hour or so.
I have some headspace questions. And yes, during my eternal build I read nearly every thread related to headspacing.

I used the gauge method to set HS (friction fit, three clicks out - I'm running the 7.62X51 SA currently on the market). The first couple shots revealed the rear of the case (just fwd of the extract groove) looked a little bulged but no split/ruptured cases- that would mean excessive HS, correct? So I went in one click, still a little bulged but not as bad and still no split/ruptured cases. Then one more click in and I had pierced primers - but the cases looked fine. HS too tight correct? So I settled for one click back out and once it warmed up, all seemed fine (two clicks out from friction fit essentially). Although it does seem the chamber leaves a mark/scratches around the circumference of the rear portion of the case - might this indicate a excessively worn chamber or something? I know, I know, shoulda took pics but I was a little preoccupied with the task at hand. I'll get some on run #2. The 1919 is a remarkable piece of machinery.

So, to sum up my questions:
Rear case bulged - excessive HS?
Pierced primers - HS too tight?
Also, is some marking on the rear of the case normal?

I'm pretty sure I'm on the right track, just wanted to check with someone with some mileage under their belt. Sure, I already got past the "build" learning curve, but ops is a whole new ballgame for me. I really don't want any brass embedded anywhere on my person
Pics and vid to follow...
TIA
mcj600

 

[loboslanding]

Congrats on the build.

Toss the gage and follow method 2 in the headspacing tutorial and you can't go wrong. The gage does not work for certain ammo. Start with only one click out past lockup and if it runs fine leave it alone. If it gets sluggish or bolt won't close after it's hot then go out one click at a time until it runs good.

The headspace should have no effect on piercing primers. Either the ammo has high primers or your firing pin has too much protrusion. Haven't seen too many firing pins with too much protrusion, but it could happen. I don't know the proper dimension, but several sources sell a protrusion gage. I'd suspect the ammo first.

Case marks are normal.

Have fun.

 

[mcj600]

Thanks (again) Lobo!
I thought about using method 2 but had that fancy HS gauge and all...
It was a good day all in all, the ol' 1919 is an impressive piece of machinery. What was even better was seeing something I built come to life
mcj600

 

[loboslanding]

Good job, sounds like all the gun needs is a little headspace tweaking and a few thousand rounds digested .