7 saum DBM Feeding Issues

jd5521

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Feb 21, 2017
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Tyler, Texas
I have a 7 saum built on a surgeon 591 that has a notched feed ramp. My issue is that I have my cartridges loaded short enough, however, after it seems that when I chamber the first round it pushes the second round forward just enough that the tip of the bullet just catches the feed ramp on the way up. This in turn happens to the other rounds in sequence. Is there something I can do to the magazine itself to where the rounds do not have so much tension against one another to prevent this and have them stay more in place. These are new Accurate Mag WSM magazines but I keep them loaded in an attempt to “loosen” the spring up but that hasn’t helped.
 

Jabot

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Sep 2, 2014
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Watching thinking of building a saum would like to no the reason and fixes
 

Steel head

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Is the tip getting caught in a gap between mag and feed ramp or is the feed ramp still over hanging the front of the mag?

Feed ramp may need deeper notching.

Mags may need lips adjusted.

On my 7 saum my arc mags were almost GTG I just had to open the overall lip to get the cases just a tiny bit higher and a bit extra opening at the front to raise the bullet up a smidge.
 

jd5521

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Feb 21, 2017
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Tyler, Texas
Is the tip getting caught in a gap between mag and feed ramp or is the feed ramp still over hanging the front of the mag?

Feed ramp may need deeper notching.

Mags may need lips adjusted.

On my 7 saum my arc mags were almost GTG I just had to open the overall lip to get the cases just a tiny bit higher and a bit extra opening at the front to raise the bullet up a smidge.
When the second round moves forward from the initial feeding of the first round, the tip slightly hangs up under the notch. I am going adjust the feed lips to see if this helps. I have another spring in another mag I just found that isn’t as stiff as the spring in this mag so I will most likely replace the springs as well to see if that easing of the tension helps to not move the below rounds so far forward. These mags don’t have binder plates so another option I thought of was fashioning one from a piece of very thin metal so I could still load to the length I want and stop the tips from being hung up. I know it’s not a huge deal to deepen the notch but if I can keep from doing that then that is what I would prefer I think.
 

iceng

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Sep 2, 2017
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Personally I’d fix the notch.
Exactly this. I had a BAT Machine action I had to notch the feed ramp on to get to feed reliably. It over hung the magazine by a millimetre or so.. stripped the gun down, Into the milling machine, notched the fee ramp, blended it and polished to suit, customer was happy with the result. It happens.. it's more a stock issue than an action or mag issue I've noticed.