the brass must be flush to the chamber face or recessed ~.001", if it's protruding from the chamber, it won't lock up well, and good, consistent lock up = accuracy. Wink
There are times...this isn't the best way to do it...
338-06 A-Squre 180 grain Nosler Ballistic Tip at 3050 fpsThe above group was shot with cases pre-stressed to fill the barrel frame gap on my 338-06A-Square...Meaning that since I have a .0015" frame gap..the cases protrude from the breech face .0015"..This is how Bob Merkur of Redding suggested it be done..and how I have done all of my Handi Rifles...Since these rifles are being closed hard...and the rim is exactly what the frame barrel gap is..they will close...only when you are using sized cartridges over the frame barrel gap will it be difficult to..or refuse to close..I get 3-5 firings before mine won't close properly....and the shoulders will need to be bumped back...depending on how hard I drive it...At most I will size the cases to be flush with the breech face...but never below...Others might..but..I never have nor will...Most handi's have very generous chamber dimensions...and I won't induce any additional head space to them...I treat all my ammunition separate for each rifle...and don't mix them..
I also check factory loaded ammunition..and separate any ammo that fall below the breech face or sit above it more than the F.B.G....I never use this ammo for shooting groups or sighting in...even with the extractor barrels...These rounds that fall below the breech face have caused more unexpected results in every Handi I have ever owned...and I won't shoot them when hunting or for any serious bench work..I usually use these factory loads for checking velocities across the chronograph.
This is something that is very easy to check before heading to the range...Try it for yourself...and you'll see...
BTW...My rifle locks up tight...and I have even wear on the latch shelf..and it is very consistent...provided that my reloading technique is too...and loading it this way...
you have to be very precise...To me...the dividends are worth the extra effort to try different techniques...
As LaOtto222 said...Every rifle is one unto itself...
So...since this is a older 7x57 Mauser ejector barrel..and you are using reloads...and you don't want to send it in to be repaired,,,Check the frame barrel gap..and try setting the head space to be exactly what the F.B.G is...provided it is under .006"..if it is at this or above...Shim the barrel to correct as described in the FAQ's...Also...index your brass so you load it exactly the same each time..and start with all of the brass to the proper trim length..then shoot the same load...I make a small scribe and load it to T.D.C. every time...
If you can't re-chamber the just fired round in the exact position and close it as you normally do..you frame is flexing too much for that load..or your lock up isn't as good as you thought..and allowing it to flex..So you can check the latch and stone it if needed...Or the latch engagement is good..and it still won't chamber..back off 2 grains of powder and check it again as above...Just because your not seeing any pressure indicators doesn't mean your not getting them...and no 2 rifles will react exactly the same with the exact same loading...
If your still having fliers that are consistent...try removing the fore-arm and shooting with out it..This will let you know if the fore-arm is effecting anything..If it shoots no different...try making a pressure point in the fore-arm with something...a couple business cards or even aluminum foil will work well enough temporarily just to see how it will react...If this helps..then a permanent solution can be made..
Good Luck
Mac