Correctable Mechanics Affect Leading / Accuracy

[Bass Ackward]

Once in awhile every blind squirrel finds a nut.

I had problems with leading on one of my Redhawks that after everything else was corrected, turned out to be an end shake problem. For those who do not understand end shake, you take your cylinder in an empty gun, place your hand over the top strap griping the cylinder with your finders and you thumb. Gently try to slide the cylinder forward and backward when it is locked in the frame. Do not confuse this with rotational movement, but check to see if you have it. If it moves at all or you can see your B/C gap change, you have end play.

The problem is that endplay will lead to increased revolver wear in the best case or cause you one of several problems. In my case, forward movement caused the cylinder to tip slightly, slamming the slug into the bottom of the forcing cone. This is where the leading always mysteriously began and built up as more shots were fired. It always started along the bottom rifling and worked it's way out finally spreading to all the rest from stem to stern. I tried fire lapping when I first got this gun because a bore scope showed it had issues in the barrel that could have caused the leading. Because of the misdiagnosis, fire lapping failed to improve accuracy or stop leading much. The only benifit was that it was easier to clean. As this play got worse resently, it started causing erratic ignition and misfires as the firing pin couldn't reach far enough forward to detonate the primer.

The problem is to decide how much end shake you actually have. You can use feeler guages and measure your barrel / cylinder gap both with the cylinder back and forward and subtract the difference. Experts claim up to .002 is acceptable.
Repair is very simple if you know how to disassemble your cylinder from your crane assembly. If you don't, there are numerous articles on the WEB about it that usually include helpful hints and parts breakouts. You add small metal shims in the form of washers between the cylinder and the crane. I bought my washers from Midway, $16 for 10. If you do not have the feeler guages to measure exactly, then you can use a trial and error method after you have purchased the washers.

To do this you disassemble and reassemble the crane and add one washer at a time and try and close the cylinder and repeat the slop test. Eventually, you will get to a point where the next one you add will either cause severe friction upon closure so that the hammer won't cock easily, or it will prevent the cylinder from closing all together. Stop. Don't force it. When I got to this point, I wanted perfection so I patiently disassembled and stoned and deburred applicable parts until I could add that last one without the closure problems. That really tightened everything up.

How much endplay was causing me misfires? About .003. I eventually used two of those .002 washers. Now I have no discernable endplay what so ever. This set the cylinder back and tightened up the action, It corrected headspace problems, made the gun time and lock up noticeably better, and C/B alignment was corrected in the vertical direction. It did not increase my barrel / cylinder gap, but it did make this distance as large as your gun will let it be. For me that is about .006. Still, it will be a consistent .006 for every chamber round the horn. Even the double action pull improved noticeably. The gun just feels more .... solid and precise.

All leading has stopped with this gun now with the ammo I developed for it for the past year. Accuracy is consistent from the first cylinder full. And I can shoot much softer lead than I was forced to use before which will save me money. Hope this helps if you have or develop similar issues.

[Topper]

Very good post;).
Thanks for the info:coffeecom

[grumpy one]

Bass, it sounds to me as if you are the person who can answer a question for me. Many years ago I bought a brand shiny new S&W 28-2, and found a problem. In some cylinder positions, the trigger stuck in the rearward position when it was pulled. In other cylinder positions it was fine. Not wanting to cause slack anywhere, I fixed it by stoning the ratchet wheel in the rear-centre of the cylinder, only touching up the teeth that were too tight. That was completely successful, leaving a tight lock-up in every position, without any tendency to stick. At the time I guessed the problem was that the feature in the centre of the cylinder that I've called a ratchet wheel was probably mounted slightly off centre, since the cylinder positions where the sticking occurred were adjacent to each other.

Since the problem was fixed by stoning, I decided it didn't really matter what had caused it, but I've wondered just the same.

Geoff

[Bass Ackward]

Since the problem was fixed by stoning, I decided it didn't really matter what had caused it, but I've wondered just the same.

Geoff


Geoff,

You apparently had a problem that you addressed which corrected your problem. I assume from your post, that you no longer have that gun or you would already know the answer to your question. If so, then we will never know. There are just too many possibilities. One thing always affects others. I have seen misalignment actually cause burrs on the area you mention as things fought to establish alignment. It's a part of normal buyer tuning these days as handguns are just thrown together. manufacturers attitudes seems to be, "Remeber, it's just a handgun". Take this Redhawk as an example, just look how .001 over what is considered acceptable caused all these issues. Boy what a difference in the feel of quality.

I am not trying to say that this is the only thing that can ever be wrong either. But $16 for these washers is cheap as opposed to possibly sending a handgun off to a professional or peddling the problem off to someone else. This was an economical correction worth trying first. Especially if you can feel that the problem IS there.

There were numerous things that I did, like waste some lino to mold special bullets for this gun. Tried maybe 10 different designs. Made sizers. Wasted (if you can call it that ) reloading supplies. I will bet that the cost if truely captured would be well over $300 trying to make this gun work. And two washers with a cost of about $2.00 saved my butt. I was trying to save others some expense, hastle, and frustration. I checked the rest of my guns and have more of those washers on order for some of those as well. They may not get attention right away, but they will be on hand for the dead times this winter.

Glad you got your problem solved Geoff.

[44man]

I had a similar problem many, many years ago with an old S&W .357. Had to make a shim back then. I think that is when I started to use STP on the pin, ratchet and front of the cylinder to prevent wear. I have yet to wear a gun since.

[Bass Ackward]

Some follow-up. Today we did no load development just worked on guns installing those washers to remove end shake. Shot before and after comparrisons using previously loaded ammo. Used a chrono where indicated. All guns were benched and bagged.

Gun #1: My tempermental Redhawk, 44 Mag: Required .004 or two washers to remove all end shake. Group size at 50 yards was 6" without any washers. Four shots you could cover with a quarter and two fliers that opened it up to 6".... and it leaded in the forcing cone something fierce. One cylinder had to be rotated around and hit twice to go off. ES was 146 fps.

Re-installed the first washer. Same 4 clustered together and still two fliers for a 6" group. Velocity of those fliers was 100 fps faster than the others on the chrono in both cases. The gun still leaded. ES was 131 fps.

Installed the last washer for a total .004. Still have about .001 play. ES dropped to 23 fps. Same four grouped less than an inch with no improvement, but fliers came way in for just under a 3" group. No sign of leading in the gun. Group size dropped by 50% and ES dropped by 75%. Maybe now I have a chance to work up a load here.


Gun #2: Dad's Redhawk, 44 Mag: Required only one washer to tighten. (using my shells) His gun was an evenly dispersed 4" before with fairly heavy leading for just 6 shots. About 3 1/2" after his washer added. Leading cut dramatically and brushed out with one pass. ES cut by 40%. He actually gets the same velocity out of 5 1/2" that mine does with 7 1/2". He needs larger boolits than I had loaded for mine, but I wanted to compare apples to apples.


Started to get really windy (35 MPH - 50MPH +) and raining.


Gun # 3: S&W Mdl 25-2, 45 AR. Required two, .002 washers to get down to .001 end play. Three washers would not close. Only shot before and after both installed because of weather. Gun leaded slightly before only on the drive side of the rifling. Group size before was 3". Dropped to 1 3/4"!!!! He's excited. No leading found. Chrono blew down twice and we put it away so no ES data here as we were trying to hurry.


Gun #4: S&W K-22, 22 LR. Required only one washer to lock up tight. Groups at 25 yards (to protect from wind) were 1 1/2" before and the same after installation. No change in group size. (Wind?) Gun never leaded before or after.


Pattern or oddity? Seems larger caliber guns benifited more? Who knows, who cares! I can live with the results! So there you have something to go on. Is it worth $16 of your money and the time to try it out? Well, you have to decide. Personally, I will never tollerate end play again. I neither saw nor felt any negative signs on any of the guns from installing these washers. Period. On the Redhawks, mechanical cycling was dramatically improved. Headspace was re-established, BC gap made consistent and it showed in ES from both guns.

[Bass Ackward]

Seeing is believing.

My Redhawk groups.



http://i146.photobucket.com/albums/r267/ba2_shoot/EndPlay.jpg

[PatMarlin]

That's amazing John. And YOU posted a picture.. :mrgreen: :drinks:

I'm gonna archive this thread. I'm checking endshakes now.. :Fire:

[Lloyd Smale]

44 man has some good advise here. Keep the ratchet and the front of your cylider pin hole oiled and it will save alot of wear and tear on a heavy recoiling gun. Ive seen perfectly good guns shoot loose in a very short time that werent.
I had a similar problem many, many years ago with an old S&W .357. Had to make a shim back then. I think that is when I started to use STP on the pin, ratchet and front of the cylinder to prevent wear. I have yet to wear a gun since.

[Bass Ackward]

Ive seen perfectly good guns shoot loose in a very short time that werent.


Lloyd,

Yes, but not necessarily. You can and will get excess wear no matter what you do or lubricate if you have alignment issues.

If you look at my pictures, I would bet that I have two chambers that are slightly out of alignment. Those two chambers throw fliers with every design and load I have tried while everything else custers. Here is a case where your "hard" bullets would outshoot soft as they could fight deformation better as they rotate or move the cylinder into alignment. Pulling the cylinder back, in the case of this particular gun, minimizes the angle required to produce alignment, so I get less deformation and thus future wear. But I could have lubricated the heck out of this gun and all I would have done was delay the break-in process.

If a gun is out of alignemnt, (most are to some degree) the bullet over time is going to force that gun to correct (wear) which is what causes most of the wear on a gun. And if you are shooting cast that is easy on barrel wear, it forces most of the wear on the mechanicals. If you firelap, you relieve the stress on the mechanicals but put most of the correction in the forcing cone. So you need to pick your poison. That's why I advocate jacketed use, at least at first, because the wear is transfered to both places as a compromise.

Quite honestly, unless your gun IS perfect, you want it to losen up, EXCEPT for end shake. Keeping the endshake to a minimum, keeps the cylinder back to the maximum where angles for bullet correction and wear are always less and always consistent. That is why guns with many rounds tend to be more accurate than they were new. And this is why I hate breaking in new handguns. This one has almost 3000 rounds through it now. At first, it started out really bad with the same load in the pictures and you would have wished that all six were on the plate. So it is getting better.

Failure to correct endshake though, will result in a really sloppy piece over time if you shoot it. And if you fire lap a sloppy piece that the position of the cylinder is always changing angles, then you get major wear in the cone. New guns need to be disassembled and cleaned often too. Because you lubricate worn metal which just makes it like a grinding compound. If the gun is perfect from the start, then by all means, keep it lubricated. But it will work it'self out no matter what you do or lube you use. When the wear becomes severe enough, the gun gets a reputation as a heavy bullet shooter as short (light) bullets will break seal in the sloppy cones. And if my bullets don't deform and break seal, I don't lead either. SO .... if I was using hard bullets, I could falsely believe that hard lead always outshoots soft lead when all hard lead does is prevent deformation from alignment issues. Sound familiar?

This is also why you never want to have custom work done on a new gun until you have a few thousand rounds through it so the Smith can visually "SEE" what needs to be corrected and how. You get a better job.

[Char-Gar]

Grumpy... Failure of the trigger to return or doing so sluggish is a problem I have seen in a number of Smith DAs. Every time the problem could be traced to a bobbed or replaced trigger return spring.

Folks like to cut a coil or two off this spring or replace it with a lighter one to reduce the SA trigger pull, but often what you discribe results.

[PatMarlin]

I guess all bets are off on the fix for sixguns. My Blackhawk has some, but it's pretty accurate.. :neutral:

[Dale53]

BassAckward;
Excellent post. This needs to be a "sticky" in my opinion.

Good stuff!
Dale53

[Pilgrim]

Any thoughts to trying a "Taylor throat" ? I wonder if it might not help a smidgeon with the alignment on those two off center chambers. I've often thought about having that throat put into my Bisley Blackhawk .45 Colt. Pilgrim

[felix]

What is a Taylor throat? Something like a 10 degree leade-in? ... felix

[Pilgrim]

felix - My understanding of the Taylor throat is that it is a short parallel section in the barrel that is at or very slightly over groove diameter, and precedes the taper of a forcing cone. The theory is the bullet is fully in the barrel and more or less aligned properly before it goes through the forcing cone and engraves the rifling. FWIW......Pilgrim

[KYCaster]

BA: I agree with Dale, "Good stuff".

Jerry

[felix]

OK, then, a freebore plus leade-in = throat. That has been around long before Mr. Taylor, right? The typical lead boolit BR gun will have a 0.10 inch of freebore just for the reasons you mentioned, Pilgrim. Thanks for the reply. ... felix

[Lloyd Smale]

I had one of my 625s and my 646 taylor throated and accuarcy with the best loads in it didnt get any better some of the loads that shot like crap did somewhat better though. Overall i thought it was a waste of money.

[Bass Ackward]

Any thoughts to trying a "Taylor throat" ? I wonder if it might not help a smidgeon with the alignment on those two off center chambers. I've often thought about having that throat put into my Bisley Blackhawk .45 Colt. Pilgrim


Pilgrim,

I have Taylor throated guns. And my other Redhawk is away getting that done as this is written. Your definition to Felix is right on. It seems to improve accuracy .... if it solves a problem. And that means that the freebore section is large enough to encompass the misalignment. What it really does do is help take the stress off the mechanicals with high pressure / velocity jacketed, because the barrel does the alignment and sizing, not the cylinder and cone. Handguns stay much tighter mechanically after this is done which is what I am after.

Where I really think Tayloring helps for lead is when you have a gun with much larger throats than the bore. Let's say .433 throats and a .429 bore. You can fill your throats with a .432 or .4325 bullet and have it lined up by the cone, transition into a .431 Taylor and a 1 1/2 degree slope down to .429. Cuts pressure dramatically with lead.

In my case, I have .432 throats with a .429 bore. The Taylor will be a 11 degree cone, transitioning into a .431 free bore of 1 1/2 calibers in length, and then tapering 1 1/2 degree to bore.

If I had a gun where my throats were within .001 of the bore and my alignment was good, there is no way I would increase bullet jump just to have a Taylor throat as you would probably see no difference in performance and may lose some velocity on account of it.

Best accuracy though is line bore chambering if you can afford it.

[Bass Ackward]

Pilgrim,

Sorry. I missed the part about Tayloring helping this gun.

Yes and no.

It would improve some maybe if I taylored at this point. If I taylored, I would need to increase boolit hardness because the bullet jump would be increased another 1" basically and the boolit be going at a higher velocity at rifling impact. So I would need to prevent stripping.

But if I just harden my bullets another 5 BHN, they would withstand the impact better now. So my best option is simply to let it break itself in some more to be able to shoot ACWW correctly. Or fire lap some more. Or shoot harder lead until it does.

I can play around with load too. That is usually another good sign a guy hasn't broken in his handgun yet as he says that his gun is finicky to load. Then at some point in the future when his gun is broken in, he goes back and tries something that failed in the passed and wonders how he missed this load the first time.

Failure to have a handgun broken in can cause you to formulate all kinds of opinions about what works and doesn't that you close the door on experimentation at a later date. Everything from powders to bullet styles to diameters etc. Same with rifles actually. When I can run ACWW upwards of 3000 fps in 22 caliber, 2600 in 30s, I marvel at someone saying lino above 2000.

Handguns will drive you crazy though if you take them seriously. Not one guy in a thousand makes it to the point where 44man is. And God bless him, I .... will be another who fails to meet his standards. It just isn't worth it to me. Get me to 2" at 50, and I will holster it and move on to the next task at hand. :grin: I can pick up a rifle if I need better.

[44man]

Bass is correct in that lube will not help if the gun isn't right to start with. However it will keep it from getting worse and after eliminating end shake is needed to keep it tight.
I used to use all kinds of gun oil long ago and found it just did not hold up. I tried grease and didn't like it either. Then I tried RCBS case lube and it worked great and when I ran out I tried STP. Both of these do a better job then anything I ever tried and also work great on cap and ball revolvers to keep the pin from fouling out.
I would not put the cylinder back in without it. STP seems to cushion the parts under recoil too.

[felix]

Yep, 44man, I second BA 's notion that your pistola experiences are second to none. Elmer, I hereby demand that you roll over. ... felix

[Bass Ackward]

I used to use all kinds of gun oil long ago and found it just did not hold up. I tried grease and didn't like it either. Then I tried RCBS case lube and it worked great and when I ran out I tried STP. Both of these do a better job then anything I ever tried and also work great on cap and ball revolvers to keep the pin from fouling out.

I would not put the cylinder back in without it. STP seems to cushion the parts under recoil too.

44,

I have been thinking about this. I would guess from your posts about lube and accuracy testing that you don't fire many rounds between cleanings. Correct?

When the high pressure from the BC gap hits that pin area, just about any lube is going to be either vaporized or blown off over time. Using your STP idea, I wondered about Slick 50 with teflon. So as the oil is removed by pressure that you still have teflon. And it's about the same consistency. On double actions, I currently use teflon on the bare metal, a light coat of grease over top of that to hold the powder, and then use molybdum disulfide powder for when the grease dries out.

Remember, while you take the cylinder out to clean a single action, double actions aren't taken apart at every cleaning. In fact, Ruger tells you NOT to break it down. I guess that means EVER! We need a more persistent lube that doesn't .... dry out. But that should work for the wear at the back of the frame area.

[felix]

Moly--yes, teflon--no. The former will bind to the metal electronically, provided you clean the gun with a strong degreaser first. You might consider a product called Molykote 321 which has, or did have, the degreaser as carrier. Just spray the stuff all over the insides of the gun. Teflon won't stick to anything, and is therefore worthless considering the firing vibrations and all. ... felix

[44man]

I have not cleaned my revolvers in the last 6 months and after thousands of shots, I just pulled a cylinder to check---there is still STP on the pin. It is dirty but still sticky. Seems as if the cylinder blast does not really get into this space. I rarely clean them unless I have lubes, boolits or loads to test.

[Bass Ackward]

This is an after action on end shake removal from 2 Ruger Redhawks, And 5 S&W revolvers. The calibers were 44 Mag, 45AR, 38Sp, and 22LR.

Sorry that this took so long to report on, but it took awhile to get descent weather to make testing fair and accurate for all of these guns and I wanted several groups from which to judge any improvement.

Every single gun increased in performance with the percentage of accuracy improvement directly related to how much the gun was out .... and .... how large the caliber was. Leading was decreased dramatically or eliminated in cases where that was a problem. In two cases, this allowed PB use at velocities never before approachable without leading. So it can save on GC costs. I can now shoot 20-1 at 1400 fps now and I still haven't seen the velocity / pressure limit for PB bullets.

The best accuracy improvement came in one Redhawk that has two misaligned chambers and the M25-2. The 25-2 was always accurate but would vasilate from a 1 1/2" to a 3/4" performer. Now it is steady as a rock at 3/4" or sometimes slightly better.

The only problem resulting from this correction has been with the 25-2 that now has super tight framespace and any unburnt powder flakes that get under the extractor will prevent the cylinder from closing. But that is operator error that keeps me grining from ear to ear.

:bigsmyl2:

[PatMarlin]

Can you post pics?... of your grin.. :mrgreen: