Reaming chamber throats gave MORE leading

[Whistler]

I have a S&W 625-8 that had tight chambers. I have to crimp really hard for my .45ACP cartridges to be able to chamber.

In IPSC shooting I use a home cast .452 230gr RN, that gave very little leading.
After reaming my chamber throats to .4525 with Dave Manson's reamers I get even MORE leading, which after just a couple of clips give me accuracy problems from 20y.

How can this be? I thought a larger chamber throat would allow for less trauma on the boolit and let it reach the forcing cone where it could enter the barrel for proper obturation.

The leading is primarily concentrated to the rear end of the barrel (near the forcing cone), but the more I shoot the more the leading spreads to the muzzle.
I size to .452 with a Lee push through sizer.

[dubber123]

I don't know why it would have increased, (doesn't make sense), but I am willing to bet you have a thread constriction just ahead of the barrel forcing cone. A careful slugging should let you know. If it is a constriction, expect a good increase in accuracy after it is gone.

[chris in va]

Are you air or water dropping? Sounds like you'll have to adjust the powder charge.

[44man]

It is not the throat size which is correct. It is something else, either alloy, lube or powder used.
Before you were shooting boolits sized by the throats and they were not in full contact with the grooves. Now the skid is giving you a problem. Your boolits are the right size so make them harder to resist the skidding. Instead of gas cutting, you are now leading mechanically. I also bet you are tumble lubing.

[44man]

Yes, look for a tight spot too.

[Whistler]

Aha, so basically I am at the most basic square one I can be at regarding "lead issues"?
I will try some different loads and see if the leading increase or decrease. I was just confounded by the whole thing with more lead after reaming.

I am using air cooled indoor range scrap (.22LR and air pellet lead), which would give a hardness of ca 10. My loads are around 16,000psi, which might be in the high end of that obturation range.

[KYCaster]

I have a S&W 625-8 that had tight chambers. I have to crimp really hard for my .45ACP cartridges to be able to chamber.



I think the crimp may be the cause of your problem. What kind of crimp are you using? Lee Factory Crimp? Taper crimp? Either one can swage your boolit smaller, causing an usdersize condition which would explain the leading.

Pull a couple of boolits and measure them to see if they are now smaller.

You also said your gun had "tight chambers" requiring the hard crimp in order to chamber correctly. You didn't say "tight throats", so did the reaming allow you to ease up on the crimp or do you still need the hard crimp?

Need more info!!!

Jerry

[MtGun44]

That is very soft lead. What mold, what lube? With throats at .4525, which I personally
think is a touch on the large size, you should be sizing to .4535 or .454. I have always
had best results with boolits .001 to .002 larger than throat size, assuming that the barrel
was properly sized -- same to about .001 smaller than throats is ideal, .002 smaller usually
works fine. If this is a tumble lube, I would suspect the lube. Please try a conventional
boolit with soft lube like LBT soft blue or NRA 50/50 formula (many brands) before you
give up. Many folks have trouble with TL, which - based on reports, seems to give marginal
lube at best. If everything is just right, it seems to work. If not, it leads like heck.

The very soft lead you have can work very well with .45 ACP at moderate velocities and
pressures. Try something like 3.5 Bullseye or 3.5-4.0 of Titegroup. Use absolute minimum
taper crimp or roll crimp with that very soft alloy and no need to go thru the feeding cycle
of a semiauto. Also, seat a boolit after accurately (micrometer NOT calipers) measuring
the diameter, then pull it - NO crimping. If it is sized down by the brass (possible at that
very soft level) you will need to alloy up a bit (50% wwts) or get a larger expander.

Lee pistol FCD is a known offender in resizing the whole round down and making the
boolit smaller than you had intended.

Good luck. Keep feeding us back info, we'll work on it.

Bill

[Whistler]

I only use Redding dies. I crimp with a taper crimp in a separate operation from the seating die.

Chambering has become A LOT better after reaming the chamber throats. Earlier the cartridges would get stuck when trying to push them in.

The only powders I have readily available are Vihtavuori, since I live in Sweden.

[markinalpine]

E-mag article from Shooting Times:
http://www.shootingtimes.com/ammunition/ST_lowdownleadfoul_201002/index.html
...
It All Comes Down To Fit :veryconfu
...

Very informative article that might answer your questions, and dispell with a lot of the BS out there.

Mark :coffeecom

[9.3X62AL]

BHn 10 is a bit soft for your application, and the lead's composition may not even be that hard if composed of rimfire and airgun projectiles. 45 ACP rifling can be fairly shallow-grooved, so a harder alloy can provide a bit more "grab" and a lot less skidding--which is what it sounds like from your description.

If possible, harden your alloy. With such low percentages of tin and antimony in your metal, I'm not sure that water-dropping would gain much hardness for you--you may need to add the elements the old-fashioned way.

I would eliminate bullet metal hardness as a factor before proceeding with fire-lapping of a possible barrel constriction.

[Whistler]

Thanks guys, I'll start with going down in velocity first and see if it makes any difference before I start with other methods.

[geargnasher]

Don't forget to slug the bore carefully (use an unsized boolit you already have, BHN 10 is fine for slugging) and try to determine if you have a restriction at the forcing cone.

Also, what's your overall length? If you had trouble chambering the rounds and opening up the throats eased this, perhaps you're seating the boolits out too far?

I would suggest NO CRIMP for the revolver with Redding dies, there should be plenty of case tension to handle the recoil of the .45 ACP, just use enough of the taper crimp to remove the bellmouth, leaving the case straight. This will reduce possible undersized boolits.
\
And has been said, FIT FIT FIT. If your boolits aren't making it all the way through the gun without encountering fit issues as some point along the way, then you'll likely have leading and accuracy problems. Fit must be proper from initial firing, through the crimp and into the throat, exiting the throat and transitioning into the forcing cone, then taking the rifling and swaging into the bore straight, then traveling the length of the barrel with good obturation (seal) and correct lubrication, and finally exiting the muzzle squarely.
If you have swaged your boolit undersize in the crimping operation, you will have problems. If the throats are too small, you will swage the boolit undersized before it has a chance to seal into the rifling, creating gas cutting and leading. If the cylinder timing or vertical alignment isn't correct, you will swage the boolit unevenly, creating a sealing gap on one side which will cause gas cutting and leading, not to mention poor accuracy and other issues. If there is a restriction at the forcing cone, the boolit will be undersized and any point beyond that, creating gas cutting and leading the rest of the way down the barrel unless it is soft enough to seal up again, but that doesn't work most times. Soft-for-pressure boolits will skid the rifling, creating gas cutting and leading, and poor lube will create friction leading, but in my experience if your .45 acp is leading the bore, THE LAST thing causing it is lube.

Gear

[MGySgt]

It is not unusal for a 45ACP to 'pull bullets' on recoil. I shoot the RCBS 230 CM from the 625-5. If I don't crimp them the 5th and 6 bullet in the cylinder will be pulled to show the crimp grove.

Shooting in one of my autos no problem - same bullet, same load.

A revolver and an aouto recoil differently in comparison to where the bullet is during the recoil.

Just my 2 cents worth.

Drew

[Piedmont]

I'm with KYCaster on this. The original poster seems confused. If the chambers are tight you don't ream the cylinder throats to fix it, you ream the chambers. Opening up the cylinder throats won't help anything chamber better unless the bullet is seated too long, and crimping shouldn't affect the chambering of rounds in that case.

[StarMetal]

Good advice here so far. You mentioned before you opened up the cylinder throats you cartridges were hard to fit. I have a Ruger Blackhawl singel action in 45 Colt and I have the extra 45 ACP cylinder. First my chambers are very very tight. Second I also have that problem of the cartridges not fitting unless I work hard and tailor loads for it specifically. What I found is it's the bullet shoulder that protrudes just about 1/32 inch our of the case mouth not fitting into the tight throats. You proved this out by opening up the throats and now your cartridges fit.

I agree to check the bore diameter where the barrel threads into the frame. Many times on revolver a tight fit constricts this area and if it is, you can make a lap to lap it out. Don't lap the entire barrel.

Your alloy is okay, but I think maybe you may be pushing it little hard. I've shot pure lead from my 45 ACP's, but you have to have everything just right.

You do need a crimp as noted, maybe not a real heavy one, but the bullets can creep out, especially that last two rounds as they are subjected to more recoil time then the others.

[Whistler]

StarMetal: You describe it far better than I did. Exactly the way I have it.

I took a careful look inside the bore with a good light. You can indeed see a slight circular pattern where the barrel meets the frame. This is the area where I have the most leading, I only noticed it because I was there scrubbing out the lead! :)

My cartridges are 1.275" as per specification from loading manuals.
The exact same load works wonderfully in my Norinco/Norconia 1911.

I have experimented some with a longer .452 boolit, and that is when I realised it was the throats that were too tight. If I chambered a cartridge, pushed on it despite the resistance and then carefully knocked it out from the other side of the cylinder, I would have clear marks on the boolit from the overly tight throat.

[StarMetal]

StarMetal: You describe it far better than I did. Exactly the way I have it.

I took a careful look inside the bore with a good light. You can indeed see a slight circular pattern where the barrel meets the frame. This is the area where I have the most leading, I only noticed it because I was there scrubbing out the lead! :)

My cartridges are 1.275" as per specification from loading manuals.
The exact same load works wonderfully in my Norinco/Norconia 1911.

I have experimented some with a longer .452 boolit, and that is when I realised it was the throats that were too tight. If I chambered a cartridge, pushed on it despite the resistance and then carefully knocked it out from the other side of the cylinder, I would have clear marks on the boolit from the overly tight throat.

So you want to make a lap and just lap out that area. Find an old cleaning brush that fits the bore. Put a lead stopping plug down the bore far enough to let the bore brush enter all the ways. Melt your alloy, preferrably some that is hard, warm up the the area of the barrel where the brush will be. Like with a hair blow dryer. Pour your molten mix into the bore saturating the brush. You don't want to come over the muzzle, but that won't hurt and it will need trimmed. Let it cool. Now do not remove the lap from the bore. Push it through to the breech end and not all the ways through. Having a bore lap that is an inch or more is preferable. With the lap protruding about 1/2 inch or so, but not all the way out, put some fine grinding compound on it evenly all the ways around. Now just lap that threaded section of barrel. After a bunch of laps pull your lap out of the barrel, BUT mark it in a manner you can insert it the same way it came out. In other worse matching the grooves and lands it was in originally. Now clean the barrel, then slug that threaded section. I know that's not easy but it can be done with a lead slug or ball that is slightly larger and small rods. Tap it out the breech end and mic it. You should have also done this before you started see your progress. You want it to be the same size as the muzzle area or slightly larger. While you're at it slug the muzzle area too. Take your time and go slow. Remember measure twice cut once. Easier if you remove the cylinder and crane assembly. Once you've done this it's a breeze to do. Ask for help with any problems.

Joe

[dubber123]

I have no doubt Joe gives a good description of how to manually lap a barrel. That said, firelapping is REALLY easy, and will give a nice smooh taper to the muzzle. Either method should work, the idea is that the bore needs to be larger on the breech end than the muzzle end. Good luck.

[38-55]

Whistler Sir,
I really think you made more of a problem for yourself than you know... You need LARGER diameter bullets, period. If you have bullets that are .452 and the throat is .4525 then you have a wobbly interface with your forcing cone/barrel. Any lapping you do may help with the leading ( but more than likely it will just move it down the bore ) but not accuracy issues.. Go with a .453 or even better a.454 diameter bullet. Or just shoot as cast diameter and see what happens to your leading.. I've been down this road and it's better to shoot a bigger bullet than wear a barrel out with lapping compound..
Stay safe
Calvin

[Whistler]

38-55: If what you say is true, it seem strange that the reamers are sold with the instruction that the chambers should be 0.0005" larger than the bullet diameter. Many sources have confirmed this, that the .452 sized bullet should easily be able to get pushed through the .4525 reamed throat. This should indicate that the bullet will not get sized down by the throats, but rather keep its intended size undeformed when it reaches the forcing cone.

Using a bullet sized .454 would end me up in what I started with in the first place: cartridges that won't chamber because the throats are too tight.

[243winxb]

Try a different lube or more lube. From Lee - Cast bullet leading

A clue to what is causing the leading is where the leading first begins to appear. If it appears near the chamber, chances are that bullet diameter or hardness are the cause.

A diameter too small and/or too hard an alloy will allow high pressure gas to leak past the bullet, which erodes the bullet and leaves leading near the chamber.

If the leading first appears on the leading edge of the rifling (if you imagine the bullet being pushed through the barrel, you will note that one edge of the rifling does most of the work of imparting a spin to the bullet. This is the edge you see when you look through the barrel from the breech end) the bullet might be too soft, and/or the velocity too high.

If the leading appears in the second half of the barrel, the bullet is running out of lube. You should see a star shaped pattern of lube accumulate on the muzzle. This is an indication that there is a little excess lube.

[MtGun44]

One more time. Boolits should be .001 to .002 LARGER than the throats.

It sounds to me like you were just seating your boolits too long and had no real
throat problem. Believing the book LOA is definitely a big mistake. The ONLY thing
that the book LOA tells you is that if you seat deeper than they did you will get higher
pressures. It has literally nothing to say about whether that LOA will work in any
gun other than the TEST BARREL that they used to do the pressure testing.

You are responsible to make the ammo that you manufacture fit your gun's chamber
and throat. If that means seating the boolit deeper, then do it. If you are using
a max pressure load, reduce the charge a bit.

And I don't care where you read .0005 larger throat is ideal. I can tell you that it very
well may work OK, but is not ideal. As a matter of fact, you may not be able to tell any
accuracy difference, but in my guns .001 LARGER is always the best accy and zero leading.
Undersized is always less accurate in my guns, in some guns it is pretty dramatic. I also
think that undersized substantially increases your chances of leading due to hot gasses
bypassing the boolit.

One possible advantage to your super soft alloy is that it may slug up to throat diameter
more easily than harder alloys. My S&W 1937 (1917) needs .455 boolits that are at least
medium hard to work well. Throats are .454 and .454 boolits were abominable - like 8"
or more at 25 yds. .455 shoots into about 2", not spectacular, but a huge improvement.

[StarMetal]

In my opinion stay away from fire lapping. First there is nothing wrong with the rest of your barrel, why wear it unnecessarily and that is what it will do in my opinion. You will notice that the rifling on the S&W 45's, that 45 Colt and in your case the 45 ACP are not very deep to start with. If you just lap that tight spot and consequently the first part of the barrel it will be tapered just fine enough. I had an older pin barrel Model 19 Smith that was tight right there because of the pressure from threading. I lapped only that out and I'll give you a list of friend that will vouch for how believably accurate that revolver is. Fire lapping will also open up your opened up cylinder throat too. Your choice, you gun.

[dubber123]

Well, I guess every one else has disagreed with Joe over something in the past, so this will be my turn... Having just finished lapping 5 different S&W revolvers, I can say that the odds of overdoing firelapping is VERY slim. It just works too slowly. I too was worried about opening up the throats during the process, but while it sounds reasonable, actually doing it proved otherwise, as NONE of the 5 revolvers showed any measurable difference afterwards. The constriction went away, the bore got shiny, the groups got much better, and leading after the forcing cone went away.

As a newly devoted fan of firelapping, I will say in your case, I would definately try a harder boolit first. I personally consider straight WW material to be about as soft as I want to go in a .45 ACP due to commonly shallow rifling that Joe mentioned. Please try some harder boolits first, and let us know how that works.

[StarMetal]

Well, I guess every one else has disagreed with Joe over something in the past, so this will be my turn... Having just finished lapping 5 different S&W revolvers, I can say that the odds of overdoing firelapping is VERY slim. There is the crucial word Slim. With the hand lap it's impossible unless like anything else you do it wrong.It just works too slowly. I too was worried about opening up the throats during the process, but while it sounds reasonable, actually doing it proved otherwise, as NONE of the 5 revolvers showed any measurable difference afterwards. The constriction went away, the bore got shiny, the groups got much better, and leading after the forcing cone went away.

As a newly devoted fan of firelapping, I will say in your case, I would definately try a harder boolit first. I personally consider straight WW material to be about as soft as I want to go in a .45 ACP due to commonly shallow rifling that Joe mentioned. Please try some harder boolits first, and let us know how that works.

Yup folks argue with me.:kidding:

[dubber123]

I believe it was Shilen that said alot of barrels were sent to their scrap barrel by their employees learning how to hand lap.....

[462]

I agree with MtGun44. My revolvers prefer a boolit that is .001" over throat size.

Start with a larger boolit and let the throat do its job, rather than hoping that a smaller boolit will bump up to fill the throat, only to be sized back down by the forcing cone.

Are the cylinder throats leaded, too?

[EDK]

I bought a pair of the original 625-2s during the late '80s "gun of the week" period at S&W. They had a problem that the chambering reamers did not have a radius on the forward end...scraped lead and you couldn't chamber after a few rounds in each chamber. The old guy who ground reamers at the factory had retired and the new guys didn't know the peculiarities of the 45 ACP in revolvers.

Remember that you're headspacing off the moon clip in this revolver. Trying to get 45 ACP cases set correctly to use without moon clips will drive you crazier! Just use the moon clip and taper or roll crimp....whatever works for you. I used a taper crimp and H&G #68 with just a bit of shoulder exposed....worked great in the 625s, my two COLTS and several 645s. Tailored for the auto and they worked in the revolver. You can load heavier boolits or exoitic shapes in the revolvers....I'm waiting for the 45 full wadcutter from NOE.

The 45 ACP revolver is the most under rated pistol. The people who have one know, but the ones that don't have one have no idea what they are missing.

:Fire::castmine::redneck:

[StarMetal]

I believe it was Shilen that said alot of barrels were sent to their scrap barrel by their employees learning how to hand lap.....

That's why Shilen firelaps huh??:Fire:

[44man]

Everyone has different opinions and results. I have zero leading and super accuracy with .430" boolits in a .430" bore and .4324" throats using BHN 22 to 28 boolits. Yes .432" boolits are more accurate but only because the boolit design and weight is different too.
Finding fast powder needs even harder boolits then slow powders has tripled my accuracy with light loads without making boolits larger too.
I will never believe in "bump up" in any shape or form as any boolit that changes shape in the throat is likely to go to pot in the forcing cone and riling.
Too many want to solve leading only and that can be done with pure lead or soft alloys but also with hard lead too. I have never found a need to make boolits larger then the throats, just another sizing operation with damage.
Understanding the revolver is the first step. The next is working with different calibers and case sizes because each is different and will cause different problems. Small cases with a pinch of fast powder that is all burnt up before the boolit moves much will mean gas escaping around it so you just have to give up something and bump up might be all you can do. A tighter fit can help to reduce leakage but in the end you give up accuracy.
Powder itself can seal the gas escape at ignition so why not find a powder that fills the ACP case to the base of the boolit?
Primers are large for the ACP case, what makes anyone think the primer pressure itself will not push the boolit into the rifling before the powder has reached full pressure? I can in no way see the boolit sitting still until the powder is burnt. Two strikes right at the start, extreme primer pressure and a fast thump from the powder.
My feeling is that the boolit has moved, increasing the case capacity before the powder reaches full burn, increasing the pressure in the chamber. Everything needs slowed down.
Now I don't have an ACP and am only thinking aloud. I have no real idea what those tiny pieces of brass do. :veryconfu
As to power lapping, it will not wear the bore. The abrasive is no longer sharp and cutting in a short distance and will only do the most work just ahead of the forcing cone. It also works on the lands and grooves evenly, not just taking the lands down. Too much lapping will choke the barrel slightly and that is good. I doubt you could measure more then .0001" difference between the front and rear after a whole lot of shots. I would never worry about 20 or so lapping shots.

[Piedmont]

My overall length has to be shorter with an ACP revolver than in my autos. If it isn't I run into chambering resistance. So I seat shorter and use moon clips. IMO that would have fixed the problem of the original poster with no reaming of any kind needed.

[StarMetal]

My overall length has to be shorter with an ACP revolver than in my autos. If it isn't I run into chambering resistance. So I seat shorter and use moon clips. IMO that would have fixed the problem of the original poster with no reaming of any kind needed.

That's exactly what I found with my 45 Ruger Blackhawk 45 ACP cylinder. I have tuned 1911's with match barrrels that have tight chambers that chamber far more loads them my Ruger ACP cylinder. I have a set of Hornady Titanium Nitride dies for the 45 ACP and cases sized with them won't fit the Ruger, but my ancient steel RCBS dies size them and they fit beautiful. For some doggone reason the chamber head space ledge won't let the wee little bit of the full diameter part of the bullet past it easily, so I have to seat them a tad deeper. With the ACP cylinder and certain good load that revolver is a tack driver!!!!

[Whistler]

Start with a larger boolit and let the throat do its job, rather than hoping that a smaller boolit will bump up to fill the throat, only to be sized back down by the forcing cone.

Are the cylinder throats leaded, too?
As I wrote earlier, if I use a larger bullet they won't fit in the chamber throats, they will get stuck before going all the way in.

I haven't noticed any leading in the cylinder.


Remember that you're headspacing off the moon clip in this revolver. Trying to get 45 ACP cases set correctly to use without moon clips will drive you crazier! Just use the moon clip and taper or roll crimp....whatever works for you.
This is my IPSC revolver, I wouldn't dream of using it without moon clips, there's really no reason not to use them.


My overall length has to be shorter with an ACP revolver than in my autos. If it isn't I run into chambering resistance. So I seat shorter and use moon clips. IMO that would have fixed the problem of the original poster with no reaming of any kind needed.
If I seat deeper I will get a bulge on the middle of the case, which would make me have to ream the chambers instead.

I am currently at a power factor of ca 200 with this load. The requirement for major is 170, but most people load to 180 to be sure that a chrony on the low side won't deem out their ammo. I have no need for 200 really, so I will go down some in velocity rather than using a harder alloy that allow me to operate at the high pressures. I will also try to back off some with the crimp.

[dubber123]

That's why Shilen firelaps huh??:Fire:

I guess they figure if they can't swing a rod with a lead slug on the end, better not give them gunpowder too... :p :smile:

[Bret4207]

You have a fit issue. Check all the information in the previous posts. Once you find the tight spot then tailor your alloy to fit your needs.

[38-55]

Whistler Sir,
Bret is right... As for the reamer folks... well they gotta sell reamers, that's their business. As for their recommendations..they answer first to their lawyers and then their customers. AND all lawyer just know you can't shoot a large bullet from a cylinder.. ( sorry if I seem cynical but I have me reasons ) Bottom line is the proof is in the performance.. So far, by listening to other folks what has it got you ? You now have a revolver that needs the cylinder/chamber opened up.. Do your self a favor and just try the bigger bullet.. At least bump the diameter of the bullet up to the size of your cylinder.. Wish I had a quick and easy fix for ya but I don't.. Once you start removing metal from a gun all kinds of problems can (and do ) crop up...
Stay safe
Calvin

[fredj338]

I have to think your alloy is part of the problem. RS of 22lr & pellets is nearly dead soft lead. I easily run 25-1 alloy, for LHP, @ 1200fps w/o much leading. The same alloy shoots wel; @ 900fps in various 45acp. I think you opended the throats just a bit too far. I had a problem w/ leading in a 45colt RBH, throats @ 0.450" I opened them to 0.4515" & leading pretty much went away. Could also be your lube & powder chpice, but I do not use VV powders so really can offer any help there.

[mpmarty]

Remember that you're headspacing off the moon clip in this revolver. Trying to get 45 ACP cases set correctly to use without moon clips will drive you crazier! Just use the moon clip and taper or roll crimp....whatever works for you. I used a taper crimp and H&G #68 with just a bit of shoulder exposed....worked great in the 625s, my two COLTS and several 645s. Tailored for the auto and they worked in the revolver. You can load heavier boolits or exoitic shapes in the revolvers....I'm waiting for the 45 full wadcutter from NOE.

The 45 ACP revolver is the most under rated pistol. The people who have one know, but the ones that don't have one have no idea what they are missing.


Yup my 45 colt Ruger came with a 45acp cylinder. It makes a dandy if noisy boolit puller.:bootgive:

[Harter66]

I have a Colts Ruger also no acp cyl yet.

I had bbl leading and 1 time heavy recoil not the next accuacy was good with the 1st cyl and dismal with the next. I was shooting comercial 255 rnfp that appeared to be the same as the factory ammo that shot great. Next thing I did was measure all over net bore, muzzle , breach,chambers ,throats ,all were text book perfect .my bullits were .4515 in throats of .4525-.453 and too hard to bump up. The 200 rn same comercial place shot great they were sized .4525 except in the 1 .453 throat that 1 went wide hi and right every time. My scrap soft boolits in a .260 rnfp drops at 454 . No bore lead no throat lead and good groups at 25 and 50 yrds.

Apples and oranges here but I have a 32 Rem and after much struggle I shortened my cases by about (not having my book handy) .07 and the chambering issues stopped . I once had some .357 brass "grow" also .

[OBXPilgrim]

If I seat deeper I will get a bulge on the middle of the case, which would make me have to ream the chambers instead.



Now just how bad does that case bulge if you seat .025"-.075" deeper? You telling us it's so bulged it won't chamber? I find that very hard to believe & wouldn't mind seeing a pic of it w/ a mic reading.

My 625 (from the 80's) has the same problem if I try to load anything as long as 1.270" & that was a Group buy 452374 copy that was a little "pointier" than the normal 452374.

Shorten the OAL, drop your charge a little if you're near max and/or to be safe. Try a few in empty cases.

I think Piedmont & MtGun44 were already onto the problem.

[XWrench3]

my smith had 2 problems (629). the first was that the forcing cone was horribly rough, it looked like the used a cutter that was sharpened with a chisel. the second was that where the barrel goes through the frame, it was tighter than crazy there. i ended up firelapping with SOFT boolits to get rid of the tight spot. i must admit that i still get a little leading with plain base boolits. but i can shoot about 70 of them through before it affects accuracy. honestly, i am afraid to go much further on my own, for fear of screwing things up. i figured i would quit before it cost me some serious dough to fix.

[Whistler]

Culprit found!

I had accidently taken my soft range scrap alloy when casting instead of the WW-alloy, that is... the loads I had previously worked up where with water quenched wheel weights.
The bullets where very soft, unfortunately I made about 2000 of them.

I lowered the load to 4.4gn N340 instead of 6.0gn and it works like a charm with zero leading. I guess I'll have to shoot in Minor factor for a while! :D

By the way... I have all my 8 revolvers' chamber throats reamed larger than the bullet. None of them have leading problems and have superb accuracy, especially my .44Mag 9,5" Super Redhawk. With 19,5gn of Vihtavuori N110 I have no problem hitting the 200 meter ram with a gas checked 240gn SWC. It is cast with the same soft lead that I accidently took for my 625 bullets, with gas checks it works great up to 1500fps.

[Bass Ackward]

By the way... I have all my 8 revolvers' chamber throats reamed larger than the bullet. None of them have leading problems and have superb accuracy, especially my .44Mag 9,5" Super Redhawk. With 19,5gn of Vihtavuori N110 I have no problem hitting the 200 meter ram with a gas checked 240gn SWC. It is cast with the same soft lead that I accidently took for my 625 bullets, with gas checks it works great up to 1500fps.



Great feedback!!! That helps us all. Mostly because it ain't quite what we thought!

A lot of interesting things came out in this thread and from people I would have never expected. I read and re-read it again just to make sure I understood.


Lets see, final conclusions were: under throat sized bullets, hard bullets in slow velocity guns, and soft lead in the magnums.

Sounds sorta bass ackwards. Must be no rules. :grin:

[Bret4207]

Makes sense. You walloped a super soft alloy really hard and the pressure was too much for the alloy to handle. Picture obturation gone mad and the alloy just falling apart. No fit there. At least it wasn't a constriction.

[Whistler]

Exactly, I was actually very relieved to find it was just a mistake of taking the wrong ingots on my side. User errors are always better than hardware errors. Unfortunately there is no CTRL + Z in real life, haha! :)