M1 carbine magazine problem

[Sonofagun]

Does anyone have a USGI spec magazine that wouldn't mind getting an inside (front to rear of magazine) measurement?

I'm having a problem w/ loading some brand name .30 carbine cartridges in a non branded (aka non USGI) 15 round magazine. I'm not sure if the problem is w/ the magazine or maybe some long OAL cartridges.

 

[Threeband]

I'm pretty sure this one is USGI. It's marked A1 on the back, and has about a 1/8" hole on the back side, near the bottom. Looks like 1.724" inside measurement.

Then I have a bunch of aftermarket mag, unmarked. I think I got them from Midway, several years ago. They've worked well. This one looks like about 1.720 inside. It's awkward trying to hold the follower down and get a decent measurement.

All my ammo is Aguila 110 gr. FMJ. OAL is 1.676.

 

[Sonofagun]

Thanks for the info Threeband!

I took the magazine apart to get the measurement because of the problem w/ the follower. Here's the measurements that I got from my magazine and ammo:

Armscor 110 gr. FMJ cartridge OAL values ranged from 1.650 - 1.658 in
Winchester110 gr. FMJ cartridge OAL values ranged from 1.661 - 1.672 in
The magazine length on both sides measured 1.676 in

There are no problems w/ loading the Armscor ammo but when loading the Winchester ammo there is binding on inserting 3-5 cartridges.