Mauser receiver drilled completely through to mount scope base

[eric123]

210011

Please ignore split cases...Bought some 8x57 brass awhile back. Found 30 or so cases head stamped REM-UMC. Looks like the owner drilled completely though the receiver, into the chamber, to mount a scope base...Disaster waiting to happen...I bet they were a bear to eject...

[DougGuy]

It's a wonder he didn't launch the scope flipping over backwards right into his cranium! Was his name Richard?

[country gent]

That looks large for a scope mounting screw hole. A 8-48 is only .156 of on the thread. It used to be when dewatting or converting to parade rifles to drill a hole thru the side of the chamber as part of the process. I'm wondering if this barrel was one of these converted barrels. I have seen them returned to "service by puhing a plug in and recutting the chamber, don't recommend it by any means but have seen it done.
Another possible explanation is. The older cup crushers used a receiver with a place to mount a copper pellet, when fired the pressure crushed the pellet increasing dia thus giving pressure information. Could these cases have come from someplace doing pressure testing?

[skeettx]

Yes, hopefully they were test cases
http://www.pcb.com/TestMeasurement/Pressure/ballistic/conformal

and

http://bulletin.accurateshooter.com/2014/10/cup-vs-psi-whats-the-difference-in-pressure-measurements/

otherwise

YUK and Double yuk!
Time for a new barrel
Mike

[Hick]

I once received a batch of 30-06 brass that was used for pressure tests-- once fired during testing. I have over 10 reloads on them now-- the testing mark gradually fades as the brass adjusts to fit the chamber, and repeated examination (outside and inside) shows no issues.

[jonp]

That looks large for a scope mounting screw hole. A 8-48 is only .156 of on the thread. It used to be when dewatting or converting to parade rifles to drill a hole thru the side of the chamber as part of the process. I'm wondering if this barrel was one of these converted barrels. I have seen them returned to "service by puhing a plug in and recutting the chamber, don't recommend it by any means but have seen it done.
Another possible explanation is. The older cup crushers used a receiver with a place to mount a copper pellet, when fired the pressure crushed the pellet increasing dia thus giving pressure information. Could these cases have come from someplace doing pressure testing?

I was thinking the same thing, that the spots look awful large but I can't really think of another thing that might cause such a marking on the case. At least I couldn't until I read the above posts. This sight really is filled with people that know all kinds of stuff.

[HangFireW8]

Pressure test cases.

[TAC14]

Pressure testing cases. Mark is from the copper crusher "pill" that starts out flush with the case and is displaced leaving the mark in the case.

These cases work just fine.

[eric123]

I hadn't thought about them being test cases...I do know the brass protrusion sticks up a few thousandths of and inch. Running a few through the full length sizing die didn't manage to squeeze them back down and have a slight "smear" to them...Either way, they are on the reloading shelf as decorations now.

[country gent]

ANother thing to remember on pressure test cases is occasionally the disk in the case is blown up into the crusher channel. SO these spots could be weak areas if full pressure rounds are used.

[Larry Gibson]

Not pressure test. Neither CUP or peizo-transducers are used on standard actions. They are used on special fixed test fixtures. Also if either were they would have been mounted in the center of the case powder capacity as per SAAMI or CIP spec. Both are very expensive to own and to use and would not have been mounted on a portable rifle.

The detent in the cases is exactly were the front screw hole would have been drilled through the barrel. I suggest the OP remove the scope and base to determine if such is the case.

[eric123]

Not pressure test. Neither CUP or peizo-transducers are used on standard actions. They are used on special fixed test fixtures. Also if either were they would have been mounted in the center of the case powder capacity as per SAAMI or CIP spec. Both are very expensive to own and to use and would not have been mounted on a portable rifle.

The detent in the cases is exactly were the front screw hole would have been drilled through the barrel. I suggest the OP remove the scope and base to determine if such is the case.

I passed a message to the gentleman I received the cases from. He said he doesn't know for sure who had the rifle in question. Is possible the cases were fired long ago...I laid a one piece base over the receiver of my friends K98 and the hole is in the exact spot under the front hole of the base FWIW...

[Geezer in NH]

Moot problem then Eh?