GSP .32 mag lips width ?
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GSP .32 mag lips width ?
Older GSP from the '70's I believe, new to me about 6 months ago.
So, I'm getting 2 or 3 "stovepipe" alabi's every 60 shot centerfire match. Gun was quite reliable until recently. Using "bumped" Speers or Lapua HBWC's seated slightly below flush C/W a roll crimp (I think)(standard Lee dies). I DID back off a bit on my crimp because some cases (brand new Lapua's) were bulging lower down and I found that backing off on the crimp just a bit stopped the bulging.
Stovepipe'd rounds seem to be caught on the case mouth at the top / beginning of the chamber (as though the front of the round were coming up a bit too soon. If I just put a bit of downward pressure on the front of the jammed round, it goes in.
I'm wondering if the front lips of my mags might be spread a bit too wide ? Mine both measure ~ .390 at the top / front.
Anyone else got calipers and care to measure / compare ?
TIA
So, I'm getting 2 or 3 "stovepipe" alabi's every 60 shot centerfire match. Gun was quite reliable until recently. Using "bumped" Speers or Lapua HBWC's seated slightly below flush C/W a roll crimp (I think)(standard Lee dies). I DID back off a bit on my crimp because some cases (brand new Lapua's) were bulging lower down and I found that backing off on the crimp just a bit stopped the bulging.
Stovepipe'd rounds seem to be caught on the case mouth at the top / beginning of the chamber (as though the front of the round were coming up a bit too soon. If I just put a bit of downward pressure on the front of the jammed round, it goes in.
I'm wondering if the front lips of my mags might be spread a bit too wide ? Mine both measure ~ .390 at the top / front.
Anyone else got calipers and care to measure / compare ?
TIA
cuslog- Posts : 28
Join date : 2018-04-26
Location : Calgary, Alberta
Re: GSP .32 mag lips width ?
At the very top front, measured from the top (I.e. narrowest point) mine measure approx .32, a little wider at the bottom of the cutout, maybe .34 -.35 or so. That is based on my 4 mags, using a Mitutoyo.
gregbenner- Posts : 738
Join date : 2016-10-29
Location : San Diego area
Re: GSP .32 mag lips width ?
Greg;
Thanks for your response.
I should have been more specific about where I was measuring. I was measuring out / out, about 3\16" down from the top.
If I measure in / in, at the very top, I get ~ .310 on one, ~.290 on the other.
The wider one is the one that seems to give me the trouble.
I guess I'll try pinching that one in a bit and see if that helps.
Thanks
Thanks for your response.
I should have been more specific about where I was measuring. I was measuring out / out, about 3\16" down from the top.
If I measure in / in, at the very top, I get ~ .310 on one, ~.290 on the other.
The wider one is the one that seems to give me the trouble.
I guess I'll try pinching that one in a bit and see if that helps.
Thanks
cuslog- Posts : 28
Join date : 2018-04-26
Location : Calgary, Alberta
Re: GSP .32 mag lips width ?
Did anything change from when it fed fine to now? Mine has been extremely reliable, when it has an occasional issue it usually means I need to clean it. PM me if it still doesn’t feed, perhaps you could call and I could do the measurements using FaceTime to insure we compare apples to apples.
gregbenner- Posts : 738
Join date : 2016-10-29
Location : San Diego area
Re: GSP .32 mag lips width ?
Greetings,
The magazine lips are spring steel and will snap off if you attempt to bend them unsupported.
I suggest isolating one magazine that functions flawlessly.
Then, compare the faulty one with the good one.
Avoid fixing things that do not need fixing.
It is possible that it is an ammunition problem. i.e. Too stiff a load or weak recoil spring causing the bolt to bounce back too quickly and the round is pushed up and out of the magazine abruptly.
Does the problem occur with factory ammo?
Cheers,
Dave
The magazine lips are spring steel and will snap off if you attempt to bend them unsupported.
I suggest isolating one magazine that functions flawlessly.
Then, compare the faulty one with the good one.
Avoid fixing things that do not need fixing.
It is possible that it is an ammunition problem. i.e. Too stiff a load or weak recoil spring causing the bolt to bounce back too quickly and the round is pushed up and out of the magazine abruptly.
Does the problem occur with factory ammo?
Cheers,
Dave
fc60- Posts : 1416
Join date : 2011-06-11
Location : South Prairie, WA 98385
Re: GSP .32 mag lips width ?
cuslog wrote:I DID back off a bit on my crimp because some cases (brand new Lapua's) were bulging lower down and I found that backing off on the crimp just a bit stopped the bulging.
Stovepipe'd rounds seem to be caught on the case mouth at the top / beginning of the chamber (as though the front of the round were coming up a bit too soon. If I just put a bit of downward pressure on the front of the jammed round,
Since you are loading the .314 size bullets, what are you sizing your brass to (what brand brass?)? in my 550, using Lapua brass, I use a +3 Lee sizing die, the standard die can result in a bulged case as it sizes the brass too small. Just a thought.
gregbenner- Posts : 738
Join date : 2016-10-29
Location : San Diego area
Re: GSP .32 mag lips width ?
Greg / Dave
Yes, I did back off a bit on my crimp because it was bulging some cases (below the base of the seated bullet). Didn't think I'd backed it out enough (maybe 1/2 a flat) to give feeding issues. Still an easy to see crimp.
Loads are a bit hotter than I like. Was set at 2.0 gr of PB but lock ring on my powder measure came loose and it crept up to ~ 2.2 gr but still didn't feel as hot as some S&B factory rounds that I have.
Gentle squeezing with needle nose pliers gave no change to feed lip spacing.
Gun came with only one mag, so one is 1970's vintage, the second one is brand new. The new one has the tighter lip spacing - the older one feels like it may have a slightly weaker follower spring in it. Its the older mag that gives the most trouble although the new one will do it too, just less often. I may take the older one apart, clean it and maybe stretch the spring out a bit. (I had to do that with one of the .22 mags).
A few things to try, thanks for the ideas.
Greg;
Brand new Lapua brass and I do have a Lee+ .003 sizing die (thanks for the idea from one of your previous posts). Being brand new brass, it would have been at whatever Lapua sizes it at. You may be on to something there. Its taken me awhile to work through 1,000 new brass to get it all to the once fired stage. I have re-sized (+.003), re-primed etc. but have not loaded any yet. Maybe I'll be able to screw in a bit more crimp on this next re-loading.
Thanks for the hint.![Smile](https://2img.net/i/fa/i/smiles/icon_smile.gif)
Yes, I did back off a bit on my crimp because it was bulging some cases (below the base of the seated bullet). Didn't think I'd backed it out enough (maybe 1/2 a flat) to give feeding issues. Still an easy to see crimp.
Loads are a bit hotter than I like. Was set at 2.0 gr of PB but lock ring on my powder measure came loose and it crept up to ~ 2.2 gr but still didn't feel as hot as some S&B factory rounds that I have.
Gentle squeezing with needle nose pliers gave no change to feed lip spacing.
Gun came with only one mag, so one is 1970's vintage, the second one is brand new. The new one has the tighter lip spacing - the older one feels like it may have a slightly weaker follower spring in it. Its the older mag that gives the most trouble although the new one will do it too, just less often. I may take the older one apart, clean it and maybe stretch the spring out a bit. (I had to do that with one of the .22 mags).
A few things to try, thanks for the ideas.
Greg;
Brand new Lapua brass and I do have a Lee+ .003 sizing die (thanks for the idea from one of your previous posts). Being brand new brass, it would have been at whatever Lapua sizes it at. You may be on to something there. Its taken me awhile to work through 1,000 new brass to get it all to the once fired stage. I have re-sized (+.003), re-primed etc. but have not loaded any yet. Maybe I'll be able to screw in a bit more crimp on this next re-loading.
Thanks for the hint.
![Smile](https://2img.net/i/fa/i/smiles/icon_smile.gif)
cuslog- Posts : 28
Join date : 2018-04-26
Location : Calgary, Alberta
Re: GSP .32 mag lips width ?
Greetings,
After you stretch the magazine spring, put it in the kitchen oven at 450 degrees for 30 minutes for stress relief.
Cheers,
Dave
After you stretch the magazine spring, put it in the kitchen oven at 450 degrees for 30 minutes for stress relief.
Cheers,
Dave
fc60- Posts : 1416
Join date : 2011-06-11
Location : South Prairie, WA 98385
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