Foxbat Posted January 25, 2015 Share Posted January 25, 2015 SVI original 170mm magazine, 9mm, 29 rounds loaded. The top round is tight at its rear, but the front, its bullet, is not under any tension, you can move it up and down with your finger. As result - it sometimes tries to go into the chamber too low, hits the ramp and stops. Replaced the spring (which was only 6 months old), same thing. Any ideas Link to comment Share on other sites More sharing options...
Sarge Posted January 25, 2015 Share Posted January 25, 2015 How does it act with 28 loaded. I can cram 29 in my mags but they don't always work. With 28 they are 100% I'm sure it's related to the tapered case of the 9mm. I wonder if trying the LEE FCD might take a tine bit of any excess taper or bulge out of the base? Link to comment Share on other sites More sharing options...
vetdocone Posted January 26, 2015 Share Posted January 26, 2015 Bend the spring so that follower nose is up Link to comment Share on other sites More sharing options...
JMike Posted January 26, 2015 Share Posted January 26, 2015 Bend the spring so that follower nose is up +1 to what he said. You might also check if the mag feed lips are within spec dimension-wise. The feed lips should measure to .350-.355 and can have a variance of .003-.005. This info is courtesy of Dawsons. Link to comment Share on other sites More sharing options...
Glk21C Posted January 26, 2015 Share Posted January 26, 2015 SVI original 170mm magazine, 9mm, 29 rounds loaded. The top round is tight at its rear, but the front, its bullet, is not under any tension, you can move it up and down with your finger. As result - it sometimes tries to go into the chamber too low, hits the ramp and stops. Replaced the spring (which was only 6 months old), same thing. Any ideas I'd call Beven and describe the symptoms. Link to comment Share on other sites More sharing options...
yoshidaex Posted January 26, 2015 Share Posted January 26, 2015 How old is the mag tube and how much use does it see? Link to comment Share on other sites More sharing options...
Foxbat Posted January 26, 2015 Author Share Posted January 26, 2015 The tube is about 16 months old, and it is used pretty regularly, it is my #1 magazine. I bent the spring, and did not see any improvement. It is sporadic with 29 rounds of JHP. With 28 there doesn't seem to be a problem. Having a CMJ bullet on top usually makes the problem much less pronounced. Link to comment Share on other sites More sharing options...
Foxbat Posted January 30, 2015 Author Share Posted January 30, 2015 Bend the spring so that follower nose is up +1 to what he said. You might also check if the mag feed lips are within spec dimension-wise. The feed lips should measure to .350-.355 and can have a variance of .003-.005. This info is courtesy of Dawsons. Is this the dimension you are talking about? If so, I am measuring .315" there, and this used to be my most reliable magazine. Link to comment Share on other sites More sharing options...
Glk21C Posted January 30, 2015 Share Posted January 30, 2015 Two things. I've learned from someone much more knowledgeable than I on mag tuning that feed lip dimensions (setting to a "set" dimension) is not the way to tune mag lips. Instead, they should be as wide as possible without having rounds slip through vertically. So slide/breech face can strip off round easily. They should be parallel to each other, not wider or skinnier at front or rear. Also, those dimensions only apply as a guide AND on STI mags. SVI mags are another animal onto themselves. What do all your other SVI mags you have measure at the feed lips? Link to comment Share on other sites More sharing options...
Foxbat Posted January 30, 2015 Author Share Posted January 30, 2015 I checked three more SVI mags that I had with me here, including one with old tube, and they all were in that range, close to .315", very far from .350". Link to comment Share on other sites More sharing options...
Aircooled6racer Posted January 30, 2015 Share Posted January 30, 2015 Hello: Set the mag lips to 0.357 front to back. Use Bolen follower and spring now TTI. I can get 30 rounds in my 170mm mags in 9mm. If you have the new style mags 30 rounds is not a problem. You MAY have to modify the bottom of the tube to stop the salt shaker from happening. Thanks, Eric Link to comment Share on other sites More sharing options...
Ace38super Posted January 31, 2015 Share Posted January 31, 2015 Dont mess with the feed lips on an SVI mag to try To set them to STI specs. Your .315 is right in the ballpark for SVI. Your problem sounds like a spring or follower issue. You might try a new Grams 13 coil with follower. Link to comment Share on other sites More sharing options...
Foxbat Posted January 31, 2015 Author Share Posted January 31, 2015 That's quite a difference of opinions: open up to .357 or stay with .315. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now