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nikonuser
04-03-2020, 01:36 AM
how do you accurately decide if the forcing cone is at fault for serious lead buildup when shooting cast in your revolver? as in 2 cylinder fulls of cheap federal 38 special 158 LRN leave the forcing cone and start of the rifling inside the barrel/frame junction plated in about a Kleenex thickness of lead?

using the old standard of worn out brass brush wrapped with a 2' long strand of wire from a chore boy has done very little in removing it. though I have seen on here the "new" practice is to cut a section of chore boy like its a piece of window screen and then put on the bore brush..


Is a "plunk test" with a factory swaged 158 grain speer swc useful?

Onty
04-03-2020, 03:46 AM
For lead removal, I doubt that anything is better than Lewis Lead Remover https://www.ammoland.com/2009/03/lewis-gun-lead-remover/#axzz6IWtgIOyb .

As for excessive leading, what is bullet hardness of those Federal 38 Special rounds? I never shoot factory 38 Specials, but from I had seen, those bullets are quite soft, most likely swagged.

Also, what is revolver? Forcing cone should be smooth. If not, take gun to a good smith and he will fix forcing cone in no time, cost is usually very reasonable. Also, check cylinder timing. I remembered some old S&W revolvers from Bangor Punta era were notorious for all kind of problems, and frequent results were lead spitting and leading.

Another issue could be constriction in thread area of the barrel. Many revolvers have that problem. And when combined with not so smooth barrel, leading is almost inevitable. Check how Marshal Stanton made a mediocre revolver into a tack driver, including fire-lapping of the barrel http://www.beartoothbullets.com/ . I think the article is "Do-It-Yourself Sixgun Kit!". Unfortunately, at this moment their server is down so I cannot check if this is right article.

Petrol & Powder
04-03-2020, 06:19 AM
I will second the vote for a Lewis Lead Remover. It is the best tool to remove lead. However, copper Chore-Boy wrapped around an old brush is a very close, and less expensive, alternate.

As for leading from factory lead RN, I'm not certain one can assuming the gun is at fault. The problem could be the gun or it could be the ammunition; not enough information there.

Biggin
04-03-2020, 07:31 AM
I've never had any good performance out of factory lead loads either. Until I tried casting my own I decided I wouldn't use lead at all. I've learned that most of them are swaged and are soft lead. I learned that the hard way. Got terrible leading in my 44s and 38s. Of course I didn't know anything about boolit fit hardness or lubrication either.

Wheelguns 1961
04-03-2020, 08:29 AM
I have had leading problems on the forcing cone and first couple inches of the barrel when the bullet diameter was too small for the cylinder throats. The gas cutting starts in the throats and deposits the lead on the forcing cone. It stops when then bullet gets in the rifling and fits correctly. Leading like you describe will also be caused by thread choke. If these are the only rounds that cause leading, they probably are too small.

Silver Jack Hammer
04-03-2020, 10:39 AM
This is why we cast boolits. In the early 1980’s I was a rookie police officer and purchased a brand new Ruger Security Six stainless and it didn’t make it through 100 rounds of department wadcutter .38 Special. I took the gun to a gunsmith, he said there was nothing wrong with the gun and he had never seen such horrible lead fouling before. He said the lead fouling tied up the gun.

I have intentionally fired my cast boolits without cleaning my revolver just see how long it will go before failing, my revolver went several months of regular shooting, and tied up from lube build up in the cylinder pawl slot in the frame. The next experiment should be done with a different lube.

Ditto on the Lewis Lead remover.

cupajoe
04-03-2020, 10:47 AM
If it's leading in the forcing cone, it's not thread choke cause the bullet has not made it to the threads yet. More than likely a soft bullet too small in diameter and a fast powder. Maybe gascutting the bullet before the bullet seals in the throat.

Norske
04-03-2020, 12:25 PM
Almost any gunsmith will have an 11 degree cone reamer. Steeper tapers often have problems with cast bullets, but work well with jacketed bullets. I used to live back-to-back with a gunsmith who had 11 degree cone reamers in common calibers. All my revolvers have the proper cone angle. It's no more than a 10 minute job for an experienced smith.

silhouette_shooter
04-03-2020, 03:34 PM
Check the cylinder throats, too big or too small will both cause this. I have a cylinder on the way back from getting its throats opened up. It will be here 8 April. It's for a spanking new S&W. I also have a WWII S&W Victory revolver that gets leaded up, the bullets were too small. Just received a proper bullet mold, (I slugged the cylinder/bore), and have made a batch of 150 grain semi wadcutters, (gun shoots 150's within an inch of p.o.a. at 50 feet), just waiting on a sizing die from Magma at this point.

nikonuser
04-03-2020, 04:21 PM
Almost any gunsmith will have an 11 degree cone reamer. Steeper tapers often have problems with cast bullets, but work well with jacketed bullets. I used to live back-to-back with a gunsmith who had 11 degree cone reamers in common calibers. All my revolvers have the proper cone angle. It's no more than a 10 minute job for an experienced smith.

there are no gun smiths in my area. There is a fool who claims to be a gun smith, but all he does is "install scopes" backwards

nikonuser
04-03-2020, 04:29 PM
I do have a bullet from a few years ago from the same lot date of federal ammo, I can cut it with a fingernail like it was a 22lr. that has the base look like it was melted.

im going to try to get some cell phone pictures of the forcing cone, and then when clean, and then with a speer 158 swc in it.

nawagner
04-03-2020, 07:47 PM
Right size cylinder throats and cut the forcing cone to 11 deg helped in my revolvers with leading and accuracy.

nikonuser
04-04-2020, 11:59 PM
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nikonuser
04-05-2020, 12:04 AM
259752

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nikonuser
04-05-2020, 12:19 AM
speer 158 grain swc. it goes into the forcing cone a tad bit, and goes rather erratic into the cylinder mouths

Bass Ackward
04-05-2020, 10:23 AM
Have you ever wondered why there isn’t one bullet design? One lube? Why this board has so many posts? A guy that can’t be lucky enough to be able to think is forced to try ( experiment ) his way to success.

But I’ll guess. The blue looks pretty shiny & that cone looks kinda virgin. Has that gun shot any jacketed or been shot much at all?

DougGuy
04-05-2020, 10:34 AM
No amount of 11 degree cutter will cure that barrel. By the time you got down to the rifling and the larger tool marks, you'd be all the way through the fire ring at the face of the barrel.

What's happening is this. Your boolits are exiting the front of the cylinder, and powder gas is cutting along side the boolits as they enter the a-hem "forcing" cone or the non-forcing cone whichever way you want to call it. That gun needs a new barrel.

I seriously doubt you could ream cylinder throats large enough to fire a boolit that would fill that void at the start of the barrel. If the diameter at the beginning of the barrel is .360"-ish you could possibly do it but now you are creating a second problem as a possible workaround for the obvious.

Silver Jack Hammer
04-05-2020, 11:14 AM
Nikonuser, DougGuy didn’t introduce himself. He is the most knowledgeable member here especially in the area of cylinders and forcing cones. Take what he says to the bank as the truth.

nikonuser
04-05-2020, 11:32 AM
Have you ever wondered why there isn’t one bullet design? One lube? Why this board has so many posts? A guy that can’t be lucky enough to be able to think is forced to try ( experiment ) his way to success.

But I’ll guess. The blue looks pretty shiny & that cone looks kinda virgin. Has that gun shot any jacketed or been shot much at all?

I like my guns CLEAN and like to see the blueing look shiny. Used enough that flame in the cylinder gap has removed the bluing on the cylinder face. And I like fondling it with an oily rag.

We can agree its a bitch to clean, so I really don't shoot it much. When I get antsy and need to shoot, I tend to take my rifle out to play. SO much easier to clean.

nikonuser
04-05-2020, 11:37 AM
No amount of 11 degree cutter will cure that barrel. By the time you got down to the rifling and the larger tool marks, you'd be all the way through the fire ring at the face of the barrel.

What's happening is this. Your boolits are exiting the front of the cylinder, and powder gas is cutting along side the boolits as they enter the a-hem "forcing" cone or the non-forcing cone whichever way you want to call it. That gun needs a new barrel.

I seriously doubt you could ream cylinder throats large enough to fire a boolit that would fill that void at the start of the barrel. If the diameter at the beginning of the barrel is .360"-ish you could possibly do it but now you are creating a second problem as a possible workaround for the obvious.

ive seen pictures on that rugerforum where guns with similar appearing forcing cones have been considered "good to go". But yeah, there be a few issues.

I had thought about making it a wadcutter gun. Had a thought that a decent HBWC would be able to offset the forcing cone issues. And so forth.

Bass Ackward
04-05-2020, 03:52 PM
What some guns get away with, others won’t. The lead in the cone can be thought of as cone repair which is why guys that competed cried when it built up so much they were forced to clean. Bullet / lube change is DEFINITELY an option if you aren’t satisfied. While powder heat that won’t melt lead will almost always melt lube that is exposed to it, thus you end up shooting an unlubed bullet up the pipe. This distance is end shake + barrel cylinder gap + cone depth. The less the angle, the deeper the cone. A wadcutter is the longest bearing length cause nothing is wasted on a nose, so it might work .... or not.

I am a stickler for clean too. I have a couple a guns with 3 - 4 thousand rounds that are due. From decades of doing this, the people with the most problems with cast are those that want to shoot cheap, those that want to shoot clean, & those that don’t shoot enough to learn the guns secret. You might be better off buying coated bullets instead of lubed “for THAT gun”. Interesting. I have never lost the bluing on a cylinder face before on any gun but I have worn the rifling away on a couple. No rules.

rockshooter
04-06-2020, 12:53 AM
the lewis lead remover kit has a small part specifically made to clean the forcing cone- takes a matter of seconds to do it
Loren