Kimber GMII feed jams with Precision 200gr SWC

[GregJ]

I thought I had a good load for my Kimber Gold Match II; Precision moly 200gr SWC, 5.4gr W231, OAL 1.245, crimp .4690 with mixed headstamp brass (except no R-P brass). This load worked great at the range with static targets, but under the stresses of a match, my Kimber became a jam-o-matic today at a match. Attached pic shows the type of jam. The round seems to get jammed going into the chamber at an angle. I absolutely know it's the ammo, because the last two stages today I used my son's ammo, which is basically the same load but with Precision's 200gr FPRN (OAL of 1.235 IIR). My GMII worked flawlessly. I'm using new Wilson ETM mags and my son was using new Wilson 47D mags.

My search turned up this post.

Interestingly, a post from superdude included the following:

1. try slightly beveling the underside edge of the hood.

2. polish the upper inside of your chamber.

3. try adjusting overall length.

4. stop using those bullets. not trying to be a smartass - i had feeding problems with the same design, tried everything, finally gave up.

AriM had some great pics showing the areas mentioned above.

My son shoots a Kimber Custom Classic Target, and his seems to run through the SWC just fine, so I pull the two appart and started comparing things. The throat of the two is pretty much the same - same angle and well polished, but I did notice the hood on his is beveled but is not on my GM.

How important is this bevel to the feed problem?

I may also polish the upper inside of the chamber as recommended.

If the OAL is much longer than 1.25 it seems the SWC hang up on the barrel hood when manually ejected (as in when showing clear), but I may try changing OAL a little.

I have a case of the SWC sitting under my loading bench, so I would like to get these to work. But in case I cant, I did order a case of the FPRN - because they do seem to work very well in my GMII, and I'll relegate the SWC to static target practice.

Any additional suggestions would be appreciated.

Edited June 26, 2011 by GregJ

[g56]

The first thing I would try is changing the seating depth, this could make all the difference in the world, but you never know till you try it.

I have a Kimber Custom Target, I've had it for about 15 years or so, it has fed everything I've thrown at it, but I've never really pushed it hard, my competition days are in the past now.

[shooter57]

Change the OAL. to the shorter length. I use 200 gr LSWC with no problems feeding or ejecting. My OAL is 1.265

Edited June 26, 2011 by shooter57

[GregJ]

Change the OAL. to the shorter length. I use 200 gr LSWC with no problems feeding or ejecting. My OAL is 1.265

1.265 is too long for my GM, the round hangs up on the barrel hood when manually cycling the slide to show clear.

I've loaded up a few rounds at the following OALs, will see how they work this weekend. Hopefully I can find the sweet spot. If not, then RNFP will be my go-to bullet for the GM.

1.240

1.235

1.230

1.225

1.220

Thanks for the suggestions.

[big_kahuna]

Just to give you a data point for consideration, I've had good reliability loading to 1.225 with 200 LSWC. Has worked well over tens of thousands of rounds in several 1911's. It might work for you as well.

Another thing you might try is to set your seating die using a factory hardball round. Hope this helps.

[GregJ]

I'm about ready to come to the conclusion my Gold Match just has too tight a chamber to reliably feed SWC bullets. I tried about 25 rnds at each of the following OALs, and still had some feed jams (releasing slide on full mag to chamber first round).

1.240 - feed jam

1.235 - no feed jam

1.230 - no feed jam

1.225 - feed jam

1.220 - no feed jam

When I got home from the range I polished the top of the chamber, maybe this will help some, but the GM runs fine with RNFP, so it looks like that's what I'll be loading for it.

[Bob DuBois]

I have a Kimber Stainless Gold Match 2 and it loves 200gn lead SWC bullets. Length is set at 1.250, crimp at.470 using a Lee first stage sizer in a Dillon 550. Load was 4.3 Clays but I had good results with 4.6 of Red Dot also.

It might be the sizing die. The Lee sizer seems to size a little tighter than some of the other sizing dies and they are in the first station of every pistol caliber I load. I use and recommend the Lee U die in 40 S@W but in 45ACP I have a standard Lee sizer, works great. case miked .467 below where the bullet is seated, Winchester case.

If you were to purchase just the sizer might try the U die. I've seen it cure feeding issues on several tight chambered pistols. Purchase it from Lee direct or EGW. Works!

[GregJ]

I have a Kimber Stainless Gold Match 2 and it loves 200gn lead SWC bullets. Length is set at 1.250, crimp at.470 using a Lee first stage sizer in a Dillon 550. Load was 4.3 Clays but I had good results with 4.6 of Red Dot also.

It might be the sizing die. The Lee sizer seems to size a little tighter than some of the other sizing dies and they are in the first station of every pistol caliber I load. I use and recommend the Lee U die in 40 S@W but in 45ACP I have a standard Lee sizer, works great. case miked .467 below where the bullet is seated, Winchester case.

If you were to purchase just the sizer might try the U die. I've seen it cure feeding issues on several tight chambered pistols. Purchase it from Lee direct or EGW. Works!

Bob, I have the Hornady seating/crimp die in my LNL set to only seat, and use an RCBS taper crimp die. Should I go tighter on the die? Someone on another forum suggesting going to .470-.471 Going to a looser crimp didnt make much sense to me.

My thought is the chamber on my GM might be a little tight, so going to a tighter crimp like .468 makes more sense.

Edited July 3, 2011 by GregJ

[shooter57]

Have you tried dropping your loads in a go-no go gauge?

[GregJ]

Have you tried dropping your loads in a go-no go gauge?

I've used the barrel, and they all drop in fine. I have a Wilson's on the way.

[GregJ]

Was at the range today and tried different loads, crimps, etc. Two things I did notice, no feed jams (3 point jam) with a Chip Mcormick mag, and when I did have a feed jam with one of the Wilson ETM, I would tap the bottom of the mag with my hand and the slide went to battery. The first round in the Wilson mag is definately pointing higher more than the McCormick mag, and I'm wondering if this is part of the issue with my GM not liking SWC. However, everything I've been reading says the ETMs were made to fix a lot of feeding issues with SWC.

At this point, I'm thinking I either change out my ETM mags for Chip Mccormick mags, or just run RNF bullets in it.

[Powder Finger]

Have you checked the extractor for proper shape and tension?

It looks like the round is not up under the extractor.

[Bob DuBois]

The extractor is the heart of a 1911 and it's well worth the time to pull the slide and see if it a little tight. The round should move under the extractor with just enough tension to hold it in place. You shouldn't see much movement in the extractor when pushing the round under it. To tight it won't feed to lose it won't eject.

I like to run 1911's wet also be sure your using plenty of oil a drop on the feed ramp and across from the extractor may help as well after setting tension.

[GregJ]

RE extractor tension, it was very loose - would not keep a 230g FMJ cartridge in place when moving the slide around. I had tightened it up a little, where I couldnt get a 230g round to fall off after moving the slide around a bit. Possibly I got it too tight? I'll check it again tonight, and loosen it up a smidge if need be. The extractor claw has not been polished, but I believe it has the appropriate angles.

I believe the pic of the round I had is, or just beginning, under the extractor. I believe this is commonly called a "3 point jam", where the round is jammed at the bullet nose top of the chamber, ramp/throat, and breachface. One time I noticed for the round to feed and slide to go into battery, a simple bump to the bottom of the mag was all it took. If it wasnt under the extractor, would bumping the mag have worked?

I am very anal about making sure my firearms are clean and well lubed, though I havent put anything specifically on the ramp or extractor. I'll try that next time.

In the mean time, I've also looked at the following:

- Still in the process of testing different OALs

- Looked very closely at the mags, feed lips, etc. Will number them and note in the future if they occur with a particular mag.

- Polished some the top of the chamber, part where the bullet nose hits when slide goes into battery.

- Begun sorting out brass from the loading process; Speer, Winchester, PMC, etc go in the "match" bucket, R-P, CBC, and a few others go into the "range' bucket. It's possible some of the feed issues I've experienced was due to using marginal brass at a match.

Thanks for the continued suggestions. Hopefully I will be able to post a resolution soon.

[Powder Finger]

Was any of this happening before you adjusted extractor tension?

Also set up the tension with an empty case, no bullet.

The bump deal you did will many time let the case feed when too much tension is present.

Do this also as a test. take the extractor out>>> feed a case from full mag>>> take mag out>>> get that case out of the chamber>>> put mag in>>>

feed next round. Do they all feed good?

If so you have a pretty good clue what to mess with.

The bottom line is that from your pic the round sould already be part way under the extractor and more perpendicular with the chamber and not stop where it did.

On the pic, if that was the only round in the mag and the mag spring was WAY weak it could cause that condition that time.

Edited July 7, 2011 by Powder Finger

[GregJ]

The FTF, no, but I was getting some FTE, and had adjusted the extractor to resolve the FTE.

Are you sure about using an empty case? Everything I've read researching adjusting the extractor said to use a loaded cartridge.

http://www.m1911.org/technic2.htm

I'll try the test sans extractor this evening.

IIRC, the pic was of a full mag that I had dropped the slide on.

Another thought, if the extractor was too tight, wouldnt this effect any bullet type? When I had the jam problem, I changed to rounds I had loaded with Precison 200gr RNF, and it ran like a champ.

The quest continues ......

Edited July 7, 2011 by GregJ

[Powder Finger]

The FTF, no, but I was getting some FTE, and had adjusted the extractor to resolve the FTE.

Are you sure about using an empty case? Everything I've read researching adjusting the extractor said to use a loaded cartridge.

Another thought, if the extractor was too tight, wouldnt this effect any bullet type? When I had the jam problem, I changed to rounds I had loaded with Precison 200gr RNF, and it ran like a champ.

On the case, it's not a big deal either way, you just don't want to set it too stiff (like so the case can't even wiggle with the bullet)

Really some people set them up with a modified case and a spring guage to get XXX ounces of tension. Never really did that myself.

I didn't catch the part about it running fine with the other bullet. Regardless the OAL and bullet may be contributing but at the point in the photo the round should be up under the extractor more.

Sometimes it's a bunch of little things added together. Do your testing with one mag only (not the worst or best acting one).

You may take some 1000 grit color sanding paper and polish the bottom edge and top of the chamber (it's amasing what that stuff does and no worry as you are not removing anything with that fine grit).

If that improves the feel then play with a little shorter OAL.

That paper works well for polishing the extractor.

Maybe post a pic of the extractor and cartridge?

[Powder Finger]

also one clarification on that link.... everything is correct except a better place to place the round to test is where it lives in real life.

EX: place the round under the extractor then slide in the barrel and put the barrel at a height thats just at the out of battery position.

That's where the round in realality will be when it's extracted. It should also pass that test with the case a little bit higher as the next round in the mag may push it up a little. (but if it passes lower but not higher then the hook or flat on the extractor ain't square)

[GregJ]

Powder Finger:

- I did the test sans the extractor, loaded 2 mags of SWC @ 1.240", and both mags worth (same mag) loaded just fine.

- I adjusted the extractor. It seemed to be a little tight (see pic-prior to any adjustment), so I loosened it up some so that a 230gr round would fall off with a light amount of jiggling. The 200gr SWC would fall off with just a little more aggressive jiggling, but still a lot less agressive that it was prior to adjustment. I used the barrel out of battery to make sure the round was in the appropriate position.

Also, I noticed a groove in the extractor, that I havent seen in other pics. I suppose it's purpose to aid in getting the extractor onto the case rim.

I hope to be able to make to the range sat and test the extractor, as well as some load variations.

Thanks for your suggestions!

[carlosa]

You might just need a new recoil spring ..

Specialy if a litle love tap is all it takes to chamber the round in.

[CocoBolo]

My OAL for Precison is 1.260, this leaves about a thumbnail thinkness of the full diameter above the rim. You might try this OAL. Based on my expierence the #38 mold bullets Precision SWC with the rounded edges feed best. Other SWC's with very sharp edges are much harder to get to feed in the gun.

[Powder Finger]

Powder Finger:

- I did the test sans the extractor, loaded 2 mags of SWC @ 1.240", and both mags worth (same mag) loaded just fine.

- I adjusted the extractor. It seemed to be a little tight (see pic-prior to any adjustment), so I loosened it up some so that a 230gr round would fall off with a light amount of jiggling. The 200gr SWC would fall off with just a little more aggressive jiggling, but still a lot less agressive that it was prior to adjustment. I used the barrel out of battery to make sure the round was in the appropriate position.

Also, I noticed a groove in the extractor, that I havent seen in other pics. I suppose it's purpose to aid in getting the extractor onto the case rim.

I hope to be able to make to the range sat and test the extractor, as well as some load variations.

Thanks for your suggestions!

O.K. now you can fix. 1st your tension right now is as light as I would go, as you can see your empty case tilt down.

The deal with the groove is where who ever fit it filed the forward bevel at the bootom of the extractor. It looks funny but causes no harm, it's hars to cut that part with out getting into the portion grooved in pic.

Noe go back to the Wilson instructions you put up.

The bottom of the hook portion of your extractor does NOT have enough radius on it.

It should basically match the bottom groove radius. So maybe go up no more that about .100 and be rounded.

You may want to round slightly the top portion of the groove bevel.(where it says gradual rounding) yours has a pretty flat angle.

Also if you have a safe side triangle file(checkering files are perfect as they are very fine) I generally try to make the hook undercut so it grabs the case a little better. It's not so much you can see it just slightly. To get what that is look down at your right hand and make your fingers bend at 90 degrees, now curl them in a little bit and thats what I'm saying about the under cut.

Also one thing that came to mind last night is you had an extraction problem prompting a tension increase.

Sometimes since extractors are springs they just go away and are very hard to get tension correct as they have lost their spring.

Also if you don't do anything yet I will try to post a good extractor shape pic tomorrow.

Edited July 8, 2011 by Powder Finger

[GregJ]

My OAL for Precison is 1.260, this leaves about a thumbnail thinkness of the full diameter above the rim. You might try this OAL. Based on my expierence the #38 mold bullets Precision SWC with the rounded edges feed best. Other SWC's with very sharp edges are much harder to get to feed in the gun.

SWC longer than 1.250 hangs up on the barrel hood when manually ejecting a round, as in showing clear at the end of a stage. This can be very aggrevating, and potentially dangerous. 1.245 is about the longest I can run in my Kimber that will cleanly eject a loaded round.

However, I did notice last night when cycling rounds through after adjusting the extractor the rounds were being ejected straight out to the right, perpendicular to the gun. Whereas previously I think they were ejecting at higher angle. Maybe the tweaking of the extractor will allow a longer AOL round to miss interfering with the barrel hood? Something else to try tonight.

Edited July 8, 2011 by GregJ

[GregJ]

Also if you don't do anything yet I will try to post a good extractor shape pic tomorrow.

That would be most benficial. Thanks

Also, the round I had in the pic was NOT an empty case, it was a 200gr SWC, that's probably the reason for the tilt. An empty case did NOT tilt like that.

[Powder Finger]

Also if you don't do anything yet I will try to post a good extractor shape pic tomorrow.

That would be most benficial. Thanks

Also, the round I had in the pic was NOT an empty case, it was a 200gr SWC, that's probably the reason for the tilt. An empty case did NOT tilt like that.

Follow, I see the bullet now. that looks/sounds about right.