MD20 Spring Tension

[itento 0]

Mike, I have two MD20's and have an identical problem with both. I'm using one of your new plugs set on 3, firing low brass mixed rounds (all heavy field loads of 6's or 7 1/2s, mod choke). Seat a fully loaded magazine. Leaning into gun, usually get a ftf on first 5 rounds followed by no ftf's. I've tried both 3 revolutions and 2 revolutions. It appears the bolt is riding over the rim and catching the shell in the magazine halfway down the round. I'm thinking the tension on the first 5 rounds is slowing the bolt down. When the pressure is less (12 or 15 rounds in mag) the bolt is not slowed?? BTW, the bottom of the bolt is relieved and highly polished. Is this a tension problem or something else?

[Bridis 319]

So you're saying that you think that the MD20 is trying to load the first several rounds faster than your S12 can recoil?

 

If so, you could always try a reduced tension hammer and/or recoil spring.

[itento 0]

So you're saying that you think that the MD20 is trying to load the first several rounds faster than your S12 can recoil?

 

If so, you could always try a reduced tension hammer and/or recoil spring.

 

I'm not sure what's happening. I only surmize that the pressure of the first few rounds is higher against the bottom of the bolt which may be keeping it from cycling completely (I did have a few failures to eject). I think if I went to 1 revolution that might fix the problem but before I do that, I was wondering if anyone else had the same problem.

[aresv 49]

Try turning your gunfixer plug down to 2. My 4-port, relieved and polished bolt, stock spring, gun will kick #8 Remington dove shot shells 6 feet to the right and forwards on setting 2 from an MD drum. Setting 3 is for vodka specials and dirty guns.