conversion magazines

I have an older Marvel Unit  1. The paperwork is from 2002. The gun shoots well, but recently have had had magazine issues. It reached the point last night in a match where after an alibi on the first Rapid target. I had two failures to feed on the second (one in each string). I drilled for this and got my rounds off but it wasn't pretty. I have been primarily using the Colt Ace magazines that came with the unit. I also have GSG metal and a Nelson plastic mag. I have to fix this. 

The question is... What magazines are people using for their conversions? Any thoughts on tuning 22 conversion magazines. I know how to do this with the high standard, but I don't know what the feed position should look like with the conversion magazine.

How old is the recoil spring? If all your mags started having problems I would look other places. Does the chamber have damage from the extractor, like my early Marvel developed?
Does it do this will all brands of ammo?

Robert, 

It might be short stroking because the 9lb spring is in there. It worked fine in the summer, but now that temps have dropped to sweater and jacket weather, it is not working as well. I think that I have an 8lb and a 7lb spring. I will find them and see if that helps.

As suggested above, I'd change the recoil spring if you haven't recently. Another thing to watch for on the Marvel is the guide rod. The spring will wear a ring on it about mid way and that seems to be a source of malfunctions.

As for magazines, some time ago Dave Ronning put me onto Promag plastic mags. I bought two and have used them for about three years now. They're inexpensive and work perfectly. Before that I wore out four GSG mags. They develop a tiny grove were the rim of the cartridge comes up against the feed lips. This causes the cartridge to hang up resulting in failure to feed.

I've used nothing but an 8# spring summer and winter. SV only of course.

Jim

jmdavis wrote:It worked fine in the summer, but now that temps have dropped to sweater and jacket weather, it is not working as well. I think that I have an 8lb and a 7lb spring. I will find them and see if that helps.

Colder weather has caused more than just a few alibi's, started using Mobil 1 in my Service Rifle years ago, stinks but worked!
  
Conversion Mags: Both Nelsons and ProMags work well in my Marvel.  Years ago when looking for a replacement mag for my Marvel I tried many and found that the ProMag to be 100% reliable for me.  Cheap too, they are under $15!  I bought 6 on sale for $11.99 ea.  I wasn't a poly mag fan (no reason just didn't seem right) but these turned me around and when I bought my Nelson and it came with poly mags I wasn't at all worried.
- Dave

Jim beat me to it.

on my aluminum slide Marvel I run an 8lb spring and Nelson mags without issue. No lockback

I shoot a Nelson. I use the reduced 8 pound recoil spring in mine with the factory plastic magazines it came with. The factory recoil spring is 9 pounds - I find 8 is more reliable with the CCI Standard ammunition I shoot. I also use a reduced weight hammer spring. 20 pounds. Factory or standard I believe is 23 unless I’m mistaken. My Nelson had fits from the very beginning and nothing I tried solved it. I sent it back to Larry and he went through the unit and polished parts and changed out springs and the extractor. When I got it back it now runs flawless. However cold wether can make any 22 I’ve seen or shot have hiccups now and then.

Mike,
You could try that GSG mag and if it doesn't feed with that then it probably is the spring weight. My Marvel seems to feed with the GSG mags the best. The metal ones are very, very reliable though. I only seem to get problems with any mag when using Aguila in practice. The dimensions of Aguila are all over the spectrum though so I know where the problem is.

Thanks all. I will test my GSG and Nelson mags and find my 7 and 8lb springs.

The 8lb  spring was already in the gun. I will test different magazines and then the 7.

I only use tuned steel mags. They control the nose of the cartridge during recoil and feed precisely. GSG and plastic mags allow cartridge to flop during recoil/cycling. Not the end of the world but not what I want in a mag.
Jon

I cleaned the gun tonight and installed the 7lb spring. I will clean the original mags well. 

Jon, any hints on what to look for with the mags. I have tuned som HS mags and read the section on tuning 45 mags in Knuhausen.

I use EGW high mag catch and have to shorten the feedlips to clear the slide. Then I bend/tune the feedlips.
Jon

Jon Eulette wrote:I only use tuned steel mags. They control the nose of the cartridge during recoil and feed precisely. GSG and plastic mags allow cartridge to flop during recoil/cycling. Not the end of the world but not what I want in a mag.
Jon

Hello Jon,

Who's steel magazines do you use?  Original Colts?  Knock-offs?

Thanks.

Jim

Here are one Ace and 3 Metalform mags.  That is a 22 calibre bit. 

Here is a link to an instruction sheet by Bob Marvel on functioning problems  - http://www.guntalk-online.com/images/Marvel_Functioning.pdf

I really appreciate this thread because not once was putting oil on the top round mentioned. Seems like a certain .22lr pistol manufactured in MA. always has the oil superstition attached to any problem.

The guide from Bob Marvel breaks down in detail what to look at. Even specifically says no oil near the bore! Find the actual problem and fix it, don't rely on superstition.

What can I say, it's just a pet peeve of mine. I watched a guy put oil on every magazine he shot at a monthly match for several years. He was always rattled about oil and never knew if the pistol would function.  Fix the damn thing and put your oil away!

Jon Eulette wrote:I only use tuned steel mags. They control the nose of the cartridge during recoil and feed precisely. GSG and plastic mags allow cartridge to flop during recoil/cycling. Not the end of the world but not what I want in a mag.
Jon

Even if I have no feed issues with a plastic magazine could the accuracy benefit from a steel magazine vs a plastic magazine?

Load a cartridge into the chamber from magazine. Hand eject and look at your bullet tip. Is it deformed at all? Tuned mags can come close to alleviating any tip deformation. You'll still have potential for x-ring accuracy at 50 yds but I just like reducing any potential issues.
Jon

One of my Marvel mag's works great the other one continues to give me a problem.  I suspect the follower.
Are the followers available separately.
Thanks
ash

Change your recoil spring every 5000 rounds.

Check your firing pin and chamber edge for damage if you dry fire without a plug. Marvel conversions were not made to dry fire without one, at least the old conversions weren’t.  Nelson conversions firing pins are fit so they can be dry fired.