Bullet diameter larger than throat question

[kootne]

Any problem with using a .431 bullet in a cylinder with .4295 throats? A loaded round chambers fine. this is in a .44 magnum Taurus Tracker, 240 grain bullet, 1/2ww - 1/2 20:1 alloy. I don't have a .429 sizer and was wondering if I really need one. I don't size any of my rifle bullets down, I always figured they are bore diameter and round when they leave the muzzle and they seem to shoot with better accuracy unsized. But regarding revolvers, the folks writing articles always say fit the bullet to the throat.

[Kosh75287]

There's a recently-started thread on here, about a shooter using .358" diameter bullets in a revolver having .356" throats and a .356" bore. They seem to be causing some leading. You might follow that one and see if any of the responses give you guidance.

It's been MY understanding that if the throat diameter is slightly larger than the bore, this gives best accuracy. If the throat and bore diameter are the same, this may give rise to less satisfactory accuracy. If the throat diameter is less than the bore diameter, this seems to make poor accuracy almost a given, unless hollow-base bullets are used. If I have this wrong, I'll defer to the more experienced revolver shooters for the correct explanation.

[stubshaft]

You are much better off with a larger throat than barrel! The problem is also that the barrels on a LOT of newer guns have thread choke (the area that the barrel screws into the frame is constricted) which creates a whole new set of issues.

In rifles I have always (and will continue to do so) sized the bullet to the chamber throat and NOT the bore size for best accuracy. In revolvers, I size to chamber throat diameter and make sure that the barrel is not constricted by either having a Taylor throat cut into it OR fire lapping the barrel. This ensures that the forcing cone is either the very same diameter of the bore or slightly oversize. Too many people pund a slug down the bore where the choke squeezes it UNDERSIZE without even realizing it.

In answer to the OP queary, I would just shoot them first and assess how accurate they are.

[georgerkahn]

Any problem with using a .431 bullet in a cylinder with .4295 throats? A loaded round chambers fine. this is in a .44 magnum Taurus Tracker, 240 grain bullet, 1/2ww - 1/2 20:1 alloy. I don't have a .429 sizer and was wondering if I really need one. I don't size any of my rifle bullets down, I always figured they are bore diameter and round when they leave the muzzle and they seem to shoot with better accuracy unsized. But regarding revolvers, the folks writing articles always say fit the bullet to the throat.

I read your query and the all-great replies, but reckoned I'd add one of my thoughts. To wit, I view the sending of any projectile down any barrel using any firearm as each a SYSTEM. You specified not the powder/number of grains. As much as I love cast bullet shooting, my thought is any requires a bit more "smarts" than sending jacketed slugs. When one "finds" the perfect match of alloyed-lead AND bullet shape AND powder brand AND powder charge AND what/which crimp AND... well -- you get the idea. Perhaps why regrettably admit I'll never even come close to that envisioned "perfect" load. BUT, again, the sizing of the slug is just one of a zillion factors!
I've loaded/shot my cast bullets a few thousands over bore in a .38-200 (.38 S&W) revolver with fair accuracy -- but quite a bit of leading. However -- it worked.
Good luck!
geo

[DougGuy]

Just send the cylinder and have it honed to .0005" larger than your boolit diameter, this way you are presenting the boolit to the bore at the preferred diameter rather than it exit the front of the cylinder at throat diameter.

[Char-Gar]

sending an oversize bullet through a smaller cylinder will work. How well it works depends on quite a few factors such as alloy temper, bullet lube, load pressure etc. If you are happy with your results, you are good to go. If you are not happy then buy the smaller sizing die.

[rintinglen]

The larger boolit will only be larger until it goes through the throat. Then it will be the size of the throat. What happens next will determine what you do after that.

[Soundguy]

Any problem with using a .431 bullet in a cylinder with .4295 throats? A loaded round chambers fine. this is in a .44 magnum Taurus Tracker, 240 grain bullet, 1/2ww - 1/2 20:1 alloy. I don't have a .429 sizer and was wondering if I really need one. I don't size any of my rifle bullets down, I always figured they are bore diameter and round when they leave the muzzle and they seem to shoot with better accuracy unsized. But regarding revolvers, the folks writing articles always say fit the bullet to the throat.

in the end.. if your throat is .4295... the bullets coming out will be too...

[45DUDE]

I'm thinking .431 J with a max load would build too much pressure but would work with lead? if you stay 2 grains under max that should work also? I would shoot some .431's with about 14 grains of 2400 with a 240 boolit and check the group and barrel for lead. If a problem post #5 has the answer if the barrel slugs ok.

[kootne]

Thanks everybody, for the thoughts in your replies. I just ordered a .429 sizing die. As a couple others mentioned I also was concerned about pressure and leading.

[DougGuy]

If you are concerned about leading then I wouldn't advise you to size to bore diameter, but it's a 44 magnum so you have ample pressure to obturate the boolit to the bore, provided the boolit is not too hard. You will know if you are sealing in the bore, it will lead if it isn't making a good seal. For this reason 99% of the shooters here prefer to size their boolits at least .001" over groove diameter of the bore, give it that extra little bit of lead for a sure seal, but your throats need to be at least the diameter of the boolit, preferably .0005" over boolit diameter.

[243winxb]

Barrel groove diameter plus .0005" Standard .430" dia. works for many.

The finished sized diameter changes with alloy. Harder= bigger.

[racepres]

Any problem with using a .431 bullet in a cylinder with .4295 throats? A loaded round chambers fine. this is in a .44 magnum Taurus Tracker, 240 grain bullet, 1/2ww - 1/2 20:1 alloy. I don't have a .429 sizer and was wondering if I really need one.

I guess being Old, and Cheap... the easiest way to Test and Evaluate, is to Use yer cylinder to Resize... Like we did Wayyyy back in the Stone Age!!!!
Imma slink off now....

[Larry Gibson]

Thanks everybody, for the thoughts in your replies. I just ordered a .429 sizing die. As a couple others mentioned I also was concerned about pressure and leading.

Many think/believe pressure and/or leading can be a problem. In actually measuring the pressure of bullets up to .003 over groove diameter in the 357 and 44 magnum cartridges I have not found any meaningful increase in pressure attributed to bullets being a bit over size. With magnum level loads the bullet is swaged down very early in the rise of pressure.

Given a proper lube, leasing is seldom caused by an over sized bullet because there is little or no gas cutting. If you get leading there is another problem, usually a lube problem. My Colt Anaconda 44 Magnum has a .429 barrel and the cylinder throats are .429 (pin gauged) also. I have shot a lot of .431 sized 429360 and 429421s through it over 22 gr of 2400 w/0 any problems. I have also pressure tested the same in my Contender test barrel with the pressures being what is expected.

Suggest you try the .431 bullets. If they pose no problems then if the .429 sized bullets do pose problems then simply go back to the .431 sized bullets.

Sometimes we worry too much about things that really do not matter.......

[black mamba]

I have fired .454" bullets in a Ruger Blackhawk in .45 Colt with cylinder throats reamed to .4525". No problems with pressure, leading or accuracy.

[kootne]

OPhere reporting back, Thanks to all. I got a .429 die and am using it. A slug of the barrel slips into a .427 die fairly freely, seems to be 5 groove so harder to mike. Anyway, I have tried a load with 11 grains of Unique with the 240 grain bullet and it shoots well, clean bore, no apparent lead. With a 2 hand hold, offhand, single action at 25 yards I got a 3.25" 5 shot group. Rolled cans with the rest of my shells. I haven't shot pistols much in the last 35 years so I was happy with that. The little Taurus is an easy thing to carry but kicks enough to make an old wrist injury remind me 11 grains was enough.