[nickcarr]

I have a Kimber Pro-Carry. I went shooting late tonight and I discovered something interesting. I took a look at one of the casings (Speer 200+P GDT HP) and saw something weird.

Now, I just installed an Ed Brown Hardcore firing pin - and I've shot it several times with the new pin - no problems. Have I looked at the brass before? I don't remember. But, I don't normally shoot +P at the range.

Anyway, the primer impact looks like a tear drop.

I'd guess that maybe the pin struck the primer fine, but the pin didn't release before the extractor/ejected pulled it out? So it got caught a bit? Is this is a normal +P affect? Is this something I should be concerned about?

I can post a pic if any one is interested...


-Nick

 

[feedramp]

I wouldn't be concerned about it. This was discussed a few weeks back. Sorry, but I can't remember the thread title, but you could likely find it with the search engine.

FYI, this occasionally happens to me when I shoot heavy loads. As I back off the charge, the teardrop changes to two distinct dimples, one large, one small. It's been happening on my M70 since I got it new back in the 1970s, and I've never had a problem.

 

[kbear38S]

The barrel is unlocking early - before the firing pin is fully retracted. Probably not a big problem but it's usually solved by replacing your firing pin spring with an extra-power spring. Wolff and ISMI both make them.

Another solution is to replace your firing pin stop with a square bottom type from EGW (http://www.egw-guns.com). They are popular with competition shooters on guns with light slides. You probably don't need it though.

 

[shane45-1911]

....and a new (or possibly higher rated) recoil spring might not hurt either.

 

[Dave Sample]

No cause for concern here. It's due to the high speed of the short slide. Springs won't make any difference. The barrel is unlocking while the primer is igniting and the firing pin is dragging a little.Won't hurt a thing.I would not change any springs in this gun unless you find it does not function. I wonder why you would replace a firing pin? I've never had one fail in 50 years.You might check and see if you put the spring in backwards. It has one end that is tight on the pin.

 

[kbear38S]

Originally posted by Dave Sample:
I wonder why you would replace a firing pin? I've never had one fail in 50 years.

You mean firing pin or firing pin springs? I've had both fail, the spring just recently. I had the slide off and decided it was time for a detail clean and the last two coils were broke off the body of the spring. I didn't have any malfunctions but I suppose it was a matter of time before I did.

FWIW, Wolff 1911 recoil springs are packed with a new firing pin spring. In that case, why wouldn't you want to change it?

 

[shane45-1911]

Originally posted by Dave Sample:
Springs won't make any difference.

Well Dave, a higher spring rate will keep the gun locked up longer, allowing the firing pin more time to retract.

 

[George Smith]

Ill back up my buddy shane here.
the shorter springs fatague faster than a std spring.
a heavier hammer spring will slow the slide down also. but may add to the trigger pull.

thanks -K

geo ><>

 

[Dave Sample]

I have built my version of the pro carry and have one soaking in the solvent tank as we speak. Pistol wrench and I named them Short Swords 6 years ago. The serial number is Eagle 2.I test fired it yesterday and runs 100%.Your suggestion that I don't know what various springs do is nonsense. I know what they do and what they don't do. George should know this too. When you change spring weights you set in motion the law of one thing affecting another and the results are seldom what you are trying to achieve. Go ahead and change springs to your hearts content.Give us a full report. Then we will know.

 

[shane45-1911]

Dave, I (we) am simply pointing out that primer smear can be corrected and it is NOT normal for a properly timed gun. As long as function is not affected, changing recoil spring to a higher rate, or even the mainspring is not necessarily a bad thing.

No offense intended.

 

[TiroFijo]

Well, I'm not an expert or a gunsmith, but this is what I think, FWIW:
The recoil spring rate does not influence much the slide velocity (and unlocking) at the initial stages, at least if you are changing for one just 2-3 lbs. heavier, and if you make a major spring rate change you are opening a can of worms. The timing of the pistol is governed by the mass of the slide and barrel and the geometry of the cam (or link) and top lugs; and of course the recoil impulse of the load. Everything else (recoil spring rate, FP stop, slide rails friction, main spring, hammer mass, etc.) helps but is secondary. If you have a much smaller barrel and slide mass than the original 1911 design the gun is always going to be on the edge with full power loads. You may try a heavier FP spring just in case it is retracting too late, or EGW square FP stop, but if you don't have other symptoms like funny recoil or vertical stringing I would just leave it alone or shoot a milder power factor.

 

[TiroFijo]

Sorry, double post!!

[This message has been edited by TiroFijo (edited 10-16-2001).]

 

[George Smith]

Well Im no expert (we all know what they are

) and Iv been waiting, NASA hasn't called so I no rocket scientist either. (nor a spell wiz)

Sometimes on the short guns, there is not much spring force right when the gun opens. Iv seen officers models that probably would not shoot up hill because they will fall out of battery. Kimber has a better spring set up though than the colt.

Tiro is on that the square stop will noticably slow the gun down out of battery, as will a heavier hammer spring.

Officers springs go away fast.

Dave, I was not trying to pick a battle with you. and I do not think anyone questions your experience. Hope not anyway, I enjoy your insights. It is fine to disagree. No offence intended. Yes a 20 or 22# spring will not make much difference when the gun just comes out of battery. but if the springs are tired (and they are short springs) it could not hurt to try. My .50 goes on the main spring.
geo ><>

 

[Bob Brown]

For Tiro Fijo. You say you're not an expert or a gunsmith, but your post is absolutely right on the money. If the timing is off, I'd just change the firing pin spring and the mainspring and have at it. That would compensate a bit for the short dwell time but wouldn't cure it. Cutting the bottom barrel lugs properly probably would. But who cares? It isn't critical anyhow.

 

[pistolwrench]

Well,
I guess I'll weigh in on this one.
I'd agree with George primarily. Officer's springs wear out in maybe 500rds and at that point contribute very little to retarding unlocking.
Kimber does not run much lug engagement in the first place, and their officer length mainsprings feel weak to me.
I'd try a stock weight, fresh recoil spring and possibly a square bottomed firing pin stop, before any other mods.


[This message has been edited by pistolwrench (edited 10-17-2001).]

 

[Ned Christiansen]

My turn! My turn!

Go here: http://www.m1911.org/images/searanim2.gif

Starts out as just a pic but give it a minute to warm up and it's an animated cutaway of a 1911 cycling. I believe it's accurate in that it actually shows the firing pin move forward and fire the cartridge, retract, and then basically try to stand still as the slide starts back, causing it to protrude. That's where the primer wipe comes from. It's probably not a big deal, honestly, and I have not seen it much, but I agree that a stronger FP spring will go a long way towards curing it. There is every reason to have these, and no reason not to-- given a normal gun in good condition. I have used them in combo with titanium firing pins with no misfire probs until I get into some really old, surplus ammo. From this I conclude that titanium firing pins probably are not the cat's buns on a carry gun, although I believe that they too would reduce primer wipe. FWIW all new Springfields come with titanium FP's, from what they were saying at the SHOT Show.

As to recoil springs changing slide velocities, etc., I agree that they probably make little difference in the first little bit of travel, but from there they make a dif. Witness a 175 SWC load at 750 FPS that will not cycle the slide far enough to eject the case, when used in a 1911 with an 18+ lb. spring, and witness, say, a bowling pin load with a 9 pound spring. That's gonna leave a mark!

As an aside, and don't try this at home, I'm sure I remember firing the first load in a 1911 with NO recoil spring, just for the hell of it. Will do it again today just to make sure. One thing I feel very safe in saying is that the system is not unlocking as the primer is being ignited; that would defy the whole short recoil principle.

 

[Dave Sample]

I agree with both Pistolwrench and George in their assessment of the lack of durabilty of short springs, etc,and know that Pistolwrench has forgotten more than I'll ever know about short slides on 1911's.I guess what I'm deperately try to say about this question is, it isn't a problem that needs solving. An ammo change will probably make it go away and as long as things are working, who cares aboput the primers on plus P ammo?

 

[Dave Sample]

One point that I forgot to mention is that when the gun fires, it's in battery and the springs aren't doing anything. the only spring that's working at that time is the firing pin spring.The gun unlocks after the primer ignites. The other springs control recoil( slide velocity) and slowing down the slide at the rear( main spring.)

 

[Ned Christiansen]

Hey Dave, I wish I'da got on this thread AFTER your last post, woulda saved me some typing because yeah, it's one of those things where if there's no problem, there's no problem. Years ago I had a customer who kept complaining that his 1911 wasn't grouping the empties-- you read right, the empties-- in a tight enough area. I put a lot of time and a few extractors into this before I decided I had to tell him he'll just have to be happy with reliability and accuracy!

If nothing else is happening, detracting from the gun's performance, I guess you could say that primer wipe is a symptom without a disease, although I can't completely banish the thought that it might effect extraction/ejection by trying to push the empty case off the breechface prematurely....?

 

[shane45-1911]

Originally posted by Dave Sample:
One point that I forgot to mention is that when the gun fires, it's in battery and the springs aren't doing anything.

Dave, I'm not a 'smith, but this simply not true. If it were, I wouldn't need to wear my safety glasses when I field strip my gun, because the recoil spring would not hit me in the eye, would it?

The recoil spring is under tension even when the the gun is locked up. The hammerspring is exerting force on the hammer, and the hammer on the firing pin stop and slide.

Still don't believe the springs aren't doing anything? Take 'em both out and cycle the slide by hand. Probably a wee bit easier, huh?