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m3 mag conversion

extxinakextxinak Member Posts: 5 ✭✭
edited March 2013 in Ask the Experts
Purchased an MPA1SST last year. .45acp carbine rifle. Emailed MPA after I was no longer able to fine magazines for this due to the proposed regulations. I asked if I could use the WWII era M3 grease guns in my rifle, and I was told yes. Purchased six of them from this forum, expecting to use them with little or no modifications needed. They are shorter, and thinner than the original magazines that are standard with my rifle. Can these be modified to work? I cant find any vids as mentioned by seller, that explain how to do this conversion.
Did I just blow my $$$?

Comments

  • charliemeyer007charliemeyer007 Member Posts: 6,579 ✭✭✭
    edited November -1
    Seems like poor performance from a current manufacture to me. I didn't find any google conversion information either, however this sums up my experience with M3 mags.

    http://www.keepshooting.com/m3-grease-gun-magazine.html

    You might be able to make them work. Depends on your skill level and tooling available for you to use. Fitting mags is almost a black art. Start with a dial caliper and a note pad to compare a good working one to each looser.

    Locking slot size and location is important.

    From your limited description I'd be looking towards several beads/bands of wire feed weld around the circumference and then flat filed to fit. You might try some heavy aluminum foil wrapped and glued as a cheap and easy function test.

    added there is a sticky at the top with pic instructions.

    So do you have a least one correct functioning mag now?
  • fordsixfordsix Member Posts: 8,722
    edited November -1
    all my macs use the M3 GG mags just what is you problem ? won;t lock up ? WW2 type GG mags are 30 rd and are robust in manufacture..just what did you buy GG aftermarket
  • extxinakextxinak Member Posts: 5 ✭✭
    edited November -1
    These m3 mags are supposed to be original, NOS magazines. Three still have the wrapper on them. As mentioned above, they are shorter in stature, so when I slide them in, they drop down. Still wont come out without using the mag release though. They are also thinner, so while inside firearm, wabble back and forth. I wonder if the original seller was wrong about caliber, and these may be 9mm mags? Just a thought. The only reason I bring this up is because when I loaded one .45acp round in the mag it was real tight. It was almost impossible to get it out as well. I am not the expert, which is why I am on here. If someone can inform me if it is possible to post pics, I would be happy to do so to help resolve the problem.
    Thank you for your replys.
  • extxinakextxinak Member Posts: 5 ✭✭
    edited November -1
    So I did a little more research/looking at these mags. The three in the wrapper match up with my original rifle mags. The three that were not in the wrapper do not match up as mentioned originally. Therefore, I am still believing that the opened mags are for the 9mm and will contact seller with pics and see about any refund/trade. Thanks for help.
  • fordsixfordsix Member Posts: 8,722
    edited November -1
    probally sent you 9mm sten mags
  • extxinakextxinak Member Posts: 5 ✭✭
    edited November -1
    Spoke to seller, and he thinks the same thing you just mentioned. The three that are in the original wrapper are m3 mags, but the three opened ones are the sten mags. We have things worked out. We were both under the impression that they were all m3's, hince the confusion on the difference, and why they were not working.
    Thanks again.
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