Throats measured, now what?

[Thor's Daddy]

I just measured the throats on my .454 SRH. They measure .4545 to .4555 (one is .4545, one .4550 and four .4555).

Where do I head from here?

Is this worthy of sending to Cylindersmith, or is the difference negligible (I'm not sure what an acceptable range would be)?

I was planning to buy a Lee mold, but now I'm assuming that such a plan wouldn't work too well (although the Lee 457-340-F might be worth a try).

When and if I order a custom die will I need the size to be .4550 (my logic would be to simply split the difference between the largest and smallest throat)?

What does one do for boolit sizing in an instance like this? I have a Lyman 450 and see that RCBS has a .455 sizer die. Would this be the correct choice? In all honesty, I was hoping to use a Lee push-through setup, but they only offer a .454 or .457 dies.

Please school me. I don't really want to go about doing this wrong and deal with months of leading and inaccuracy as a consequence.

[PacMan]

I will let the guys that have more experience thanme answer your question on the throat size.
I will give my input on the sizinf die. If you want to use the Lee die just pick the .454 and lap it out a little. They are real soft so go easy.

[Thor's Daddy]

...When and if I order a custom die...

Arrgh! That should read custom MOLD, not die.

[GaryN]

You should also slug the bore before you make a decision. What if for some reason your groove size was bigger than your throats. There is a sticky somewhere about slugging your bore. You may as well check for a thread constriction where the barrel screws on while you're at it. You do that mainly by feel when you are slugging the bore.

[MtGun44]

Split the diff at first. You need to try .001" under, on and .001" over and see how it
works. I would not open up the throats with that small difference unless you see
something serious on the targets the forces you to deal with it.

Bill

[jwp475]

I just measured the throats on my .454 SRH. They measure .4545 to .4555 (one is .4545, one .4550 and four .4555).

Where do I head from here?

Is this worthy of sending to Cylindersmith, or is the difference negligible (I'm not sure what an acceptable range would be)?

I was planning to buy a Lee mold, but now I'm assuming that such a plan wouldn't work too well (although the Lee 457-340-F might be worth a try).

When and if I order a custom die will I need the size to be .4550 (my logic would be to simply split the difference between the largest and smallest throat)?

What does one do for boolit sizing in an instance like this? I have a Lyman 450 and see that RCBS has a .455 sizer die. Would this be the correct choice? In all honesty, I was hoping to use a Lee push-through setup, but they only offer a .454 or .457 dies.

Please school me. I don't really want to go about doing this wrong and deal with months of leading and inaccuracy as a consequence.



.455 would work perfectly

[454PB]

What method did you use to measure the throats?

Those are really big throats for a SRH.

[9.3X62AL]

What method did you use to measure the throats?

Those are really big throats for a SRH.

My thoughts too. See if you can hunt up a set of pin gauges to verify your findings, if you slugged to get those readings. A caliper works for case length, but a GOOD micrometer is required for accurate slugging.

[Thor's Daddy]

What method did you use to measure the throats?

Pin guages.

When I first measured them I used my caliper and was getting readings of around .4555 to .456 or some such. It kinda freaked me out. The next day I went back and they measured around .453-.454. Obviously using calipers to get an accurate reading isn't really accurate.

I figured I'd better get a set of gages, so I ordered .452-.457 in .0005 steps from Meyer Gage (http://gageshop.com/).

When I sat down today to measure them the cuss words just kept piling up as I slid a bigger and bigger gage down each throat.

I know folks have mentioned slugging the bore too, but I can't imagine it running .456 or larger. If it does I'll probably just see if Ruger will fix it.

[Ed K]

Never mind how the bore measures. I'd get the cylinder fixed. I know you could live with it but... (this is coming from a guy who has taken a loss, traded or sold more than one 45 chambered firearm because it wasn't right).

On another note I've called and was nice to the person to whom I related the out of tolerance (but marginally so) conditions on three revolvers from three different manufacturers in the past year and in each case they provided 100% satisfaction. Give it a try.

[9.3X62AL]

Sounds like it's big. Diametrically opposed to times past, when "too small" created a cottage industry in the aftermarket.

.455" would be my first try, and good luck finding a mass-market pistol mould with those specs. I know that slugging the bore is another step to take before shooting the revo, but it might guide your mould purchase. If the grooves are .453"-.455", the sharp-shouldered SWCs might work well. If the grooves are more like .451"-.452", a shoulderless round flat nose might give better results. These are only "rules of thumb", and ultimately you'll need to actually fire the gun with a critical eye to learn its preferences.

That fat 45 mould you metioned may be a good first sample. I've run RCBS 300 FN meant for (but too small for) the 45-70 through my 45 Colt Bisley with throats at .453" and the boolits sized at .454". They shot quite accurately, but pretty high relative to the iron sights. A little "Tennessee elevation" (related to "Kentucky windage") got hits on coyote-sized iron cutouts at 100 yards for me pretty consistently. These were running about 1100 FPS, and while not punishing......they did let you know that the primers lit off.

[Thor's Daddy]

...On another note I've called and was nice to the person to whom I related the out of tolerance (but marginally so) conditions on three revolvers from three different manufacturers in the past year and in each case they provided 100% satisfaction. Give it a try.


I've been sitting here at work thinking this over for the last couple hours and I think I'll give them a buzz tomorrow. I'm generally a nice guy and besides, I'm too stupid about guns to get mad about it.

When I had a problem with my Smith, their customer service was completely on top of it. It was FedEx'ed the next day on their dime and came back a week later with a brand new barrel.

It certainly can't hurt to call.

[runfiverun]

can you even chamber a 455 boolit...
a mold that big won't do much good if you can't.
i'd just try slinging some 452 or 453 boolits first.
the 454 is specced at 452 just like a colt.

[jwp475]

can you even chamber a 455 boolit...
a mold that big won't do much good if you can't.
i'd just try slinging some 452 or 453 boolits first.
the 454 is specced at 452 just like a colt.



I chamber and shoot hard cast bullets sized to .454 in FA-83'. I am rather sure that a .455 will chamber in a RH or SRH

[44man]

I chamber and shoot hard cast bullets sized to .454 in FA-83'. I am rather sure that a .455 will chamber in a RH or SRH
Most SRH's have minimum chambers. I have never been able to chamber my cases shot from a SBH in any SRH. I had to keep cases separate. .44 of course.
I would not worry much about the throats as long as all are larger then groove size.
Too large can be an accuracy problem but not like too small is.
Find what shoots best, I don't think a boolit will complain over .001" difference.

[454PB]

I can't even chamber a round using a boolit sized over .452" in my Ruger SRH or FA 83. My Taurus RB has .001" larger throats, so it will take a .453" boolit if I really push hard as they are chambered.

[Iron Mike Golf]

SAAMI spec for throats of the 454 Casull is .4525 to .4565.