MDT polymer mags

1stnlast59

Private
Minuteman
May 25, 2018
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5
I bought some mdt poly mags on Black Friday when I bought a LSS chassis from them for my model 7. When I got them in I noticed that the overall length capacity of them wasn’t even the full length suggested for 6.5 creedmoor of 2.825. Actually I measured on about 2.813. I took one apart and noticed that the one end was really thick. But the thickness goes all the way to the bottom so it can’t be trimmed. Anyone else had this issue or has anyone used these mags for 6.5?
 
I bought some mdt poly mags on Black Friday when I bought a LSS chassis from them for my model 7. When I got them in I noticed that the overall length capacity of them wasn’t even the full length suggested for 6.5 creedmoor of 2.825. Actually I measured on about 2.813. I took one apart and noticed that the one end was really thick. But the thickness goes all the way to the bottom so it can’t be trimmed. Anyone else had this issue or has anyone used these mags for 6.5?
I have a CTR 6.5 in my LSS G2 and the mdt polymer loads and functions great.
So do the metal mags....
 
I bought some mdt poly mags on Black Friday when I bought a LSS chassis from them for my model 7. When I got them in I noticed that the overall length capacity of them wasn’t even the full length suggested for 6.5 creedmoor of 2.825. Actually I measured on about 2.813. I took one apart and noticed that the one end was really thick. But the thickness goes all the way to the bottom so it can’t be trimmed. Anyone else had this issue or has anyone used these mags for 6.5?

Hey, sorry to hear that you've run into some issues with our mags and those definetly sound out of spec. Thanks for tagging me in @jstuck624 !

If you could take a photo of the mag from the top down view I might be able to see if the polymer at the front looks abnormally thick. The OAL in our polymer magazines should be closer to 2.860", which is more than long enough to run factory 6.5 Creed. I filed out a polymer mag a long time ago to run 143 ELD-X's at 2.890" so it can be done. Worst case, we may have to just switch out the mags for you, but it's odd that they're so short!
 
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The mdttac website states max oal is 2.800 in the 308 mags
 
They emailed me back just a bit ago and told me this. I missed it somehow it showed a short description and didn’t know there was a detailed description on down under the advertisements for other things they sell. That’s my fault. I guess I’ll try to sell them. And buy some others that will work with 6.5 spec overall length. I guess I assumed that it showed for 6.5 creedmoor it would at least run factory spec’ed rounds.
 
Yea, I figured it out when I did the same thing. I bought two though, so I am doing my best to try and file out enough material in one for clearance. I have a metal one on backorder, but I understand I have to modify it to even fit in my rifle
 
You know what, I stand corrected. I was under the assumption that our polymer magazines were able to run 2.860" max COAL, but the website very clearly says 2.800". I have run longer rounds out of it, and the factory rounds will cycle no problem, but handloaders are going to have to take a file and modify them to ensure they run properly.
 
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That 2.825 is the Maximum saami spec length and not what you'll find in factory ammo.
I've measured about 7 different factory rounds and they all measured 2.80 and a few thousanths in change and all have functioned flawlessly in the polymer mags......
 
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That 2.825 is the Maximum saami spec length and not what you'll find in factory ammo.
I've measured about 7 different factory rounds and they all measured 2.80 and a few thousanths in change and all have functioned flawlessly in the polymer mags......

Same here. I have several MDT polymer mags. I use 308, 6.5 Creedmoor and 243 in them. All the factory 140 gr 6.5 creedmoor ammo I have tried works flawlessly in them. All this ammo has measured 2.8 OAL. If you get factory ammo that is longer my guess would be it was out of spec for the round. I would double check the length of your ammo. Now if you are handloading that is another story.
 
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You know what, I stand corrected. I was under the assumption that our polymer magazines were able to run 2.860" max COAL, but the website very clearly says 2.800". I have run longer rounds out of it, and the factory rounds will cycle no problem, but handloaders are going to have to take a file and modify them to ensure they run properly.

I’ve been able to get up to 2.815 to load and feed reliably. I haven’t tried filing because it looks to me like the limit was the thickness of the wall of the mag, and not some lip that could be filed.