.44 Special Flat Top: .432" Cylinder, .4295" Groove. What to do?

[35 Whelen]

Just got in a Flat Top .44 Special today and of course had to shoot it. First load was 7.5 gr. Unique with a RCBS 250 KT @ 260 grs., 11.5 +/- BHN sized .430" and an NOE 429421 @ 258 grs., 12 +/- BHN sized .430" At 25 yds. accuracy was so-so at 3" +/-.

I slugged the cylinder mouths and came up with .432" or maybe a shade more. Groove diameter is .4295" with a very slight constriction in the frame...not much, just a little resistance when pushing the slug through. Bore is mirror shiny.

After slugging, I bumped the load up to 8.0 grs. in hopes of better obturation and with the NOE bullet and got 2.5" @ 25 yds.

I wish the cylinder mouths and the groove diameter were closer together. Is the .432" cylinder mouths typical?

I'm thinking of fire lapping the barrel to remove the slight restriction. Would this possibly help?

Would it be worth buying a nother cylinder in hopes of smaller diameter cylinder mouths?

Thanks!
35W

[Catshooter]

I would only change one thing at a time.

I have a Smith in 45 Colt that has .456 throats and a .452 bore. I cast a 454424 that drops them largish, .457 so I size them to .456. When they hit the bore they size down nicely and shoot very well.

Four three two is a pretty big mould but worth finding if you can.

Good luck.


Cat

[35 Whelen]

Thanks for the reply. My NOE mould drops them right at .432", but the largest sizing die I have for my Star is .430. I have a .431" for my RCBS Lubrisizer that I suppose I could lap out to .432"...

35W

[Lefty SRH]

Is the .44 FT a Ruger? If so .432 may be a little big. My experience Rugers typically run .431", atleast all my .44s have been .431" I'd buy a .432 die, lube em and shoot em.

[35remington]

Don't size them. Pan lube or tumble lube them and see if accuracy improves, then lap out the sizer if needed. Your situation really isn't that bad and more desirable than too small cylinder throats.

[Silver Jack Hammer]

I've got a Colt SAA with .427" bore and .434" cylinder throat, then another Colt SAA with .429" bore and .430" cylinder throats. Using a 2 hand hold off hand at 25 yards I can't get the latter to out shoot the former. I'd be happy with the dimensions and the choice of boolit. I don't get the best accuracy with Unique. Try some Blue Dot, it's great for higher velocity loads but the muzzle flash is too bright for dim light conditions. Then I've got one 7 1/2" Colt .44 Special that I bought to shoot 2400 in, it shoots well with Unique, Blue Dot and Bullseye but will not group with 2400.

[runfiverun]

i need to have my stainless 44 specials cylinder throats opened up.
the ones on my blued one come in a tick over 430.
if i swap the cylinders i get spectacular accuracy from the stainless gun.

i think i would try a harder alloy before i got too worked up.

[Piedmont]

If you do not want to lap out your .430" die, Lyman makes a .431 and Buckshot will make you whatever diameter you want (.432 in your case).

[GaryN]

I had Buckshot make one for me. It measures .4325. He does a great job. I don't think your gun is that far off. I would just shoot it.

[MtGun44]

Don't size them. Lube and shoot at .432. If you have to have a die, open one up with
a slotted dowel and 240 wet or dry sandpaper and a drill. Having to size down the
boolit a whole .0025 as it hits the forcing cone is not much, fit your boolit to the throats
and it should do well. May have to go .001 over throat for best accy.

Bill

[fecmech]

I have an old 3 screw SBH with .433 throats and .429 groove. I "beagle" and size to .433 for best accuracy. You should do just fine with your as cast .432.

[Larry Gibson]

Don't size them. Pan lube or tumble lube them and see if accuracy improves, then lap out the sizer if needed. Your situation really isn't that bad and more desirable than too small cylinder throats.

+1.

Since your mould drops them at that diameter hand or pan lube some and try over the 8 gr Unique load. Be advised that is over +P psi and into low end Magnum range. Frankly I'd try both sizes over 5 gr of Bullseye which duplicates the standard 44 SPL load. It has always been accurate for me.

Larry Gibson

[44man]

No, no, the gun is really OK and will shoot. I don't see why a .430" boolit will not shoot unless too soft, your boolit might be slumping. You can go all kinds of sizes but if slump is a problem, it will not go away. OBTURATE, WHAT IS THAT? Too common a solution that does not work. I have grown to hate the premise.
If no leading, don't worry about a tiny restriction at the threads. Power lapping will not hurt a thing. But you are stuck with BHN and after lapping you will not see a change.
Call me a nut but make the boolits from water dropped WW metal to see what happens.
I worked with a Keith in the .44 and found the harder I went, the more accurate the gun was and 28 to 30 BHN shot better groups at 50 then soft did at 25.
My SBH has .4324" throats and a .430" groove and will shoot 1-1/4" at 100 and has done 1-5/16" at 200 yards with .430" boolits.
I will be the last person on earth to tell you that you need a new cylinder, your alloy will fix it.
Throat size does work but not with slumping or skidding boolits. Obturate to fit---NO! I wish that stuff would go away.
Look at this, 3 shots off hand at 100 yards with a boolit that is average .429" to .430" out of my gun with the .4324" throats and a .430" groove.

[felix]

My faith is restored! I see those pesky beer cans, the only target worth bragging about! Well, shotgun shells instead when the gun is scoped. Steel plates are 800 yard stuff for the Wyoming plains. ... felix

[44man]

My faith is restored! I see those pesky beer cans, the only target worth bragging about! Well, shotgun shells instead when the gun is scoped. Steel plates are 800 yard stuff for the Wyoming plains. ... felix
I don't know if you are funning my friend! :mrgreen:
I will always feel too much is written into finding accuracy because it is easier then the billion ideas. Too much hoopla that is not needed. To spend more money on a good gun looking for what you can solve at the bench really hurts me. In 99% of the time, a custom $5000 revolver will not shoot better. They only LOOK better.
You know me, I will never tell anyone to spend money not needed.

[W.R.Buchanan]

Both my BH and SBH have .429 bores and .430-1 throats. My Mihec mould drops at .434 so I size these boolits at .431 and they shoot fine.

The general concensus among them that knows is to size to the cylinder throats. Even if the boolit is .002-3 above the bore size it will still go thru the hole just fine. Most "normal" loads in this class of cartridge are between 15-20K psi and .003 of lead doesn't stand a chance against that kind of pressure. Plus it seals the barrel better and helps prevent leading.

Preventing blow by at the chamber is the best way to prevent leading problems. Sealing the throat with a tight fitting boolit is the way to do this.

Randy

[rintinglen]

My own Flat Top is by a considerable margin the most accurate .44 special I've ever shot and the specs on mine mirror yours, save that my bore runs almost exactly .430. .431 dia 429-421's cast soft over 6.5 Unique and bingo, one hole, 50 ft, groups. 5.0 grains of Red Dot does just about the same. It also likes the 429-383 sized .431 over either of the above loads.

[monge]

Had the same problem with my flattop 44man hit it right on the head. Your boolits might be to soft I always sweeten my lead pot of ww with a couple sticks of lino!