Does .001 make a difference????

[abunaitoo]

So I have a .358 and a .361 sizer.
I would like to go a little bigger than .358, but the .361 will not chamber.
So I'm looking to get a .359 sizer.
Worth it, or .001 would make little difference?????

[tazman]

What gun/cartridge are we talking about?

[6bg6ga]

What gun/cartridge are we talking about?

Kind of hard to read between the lines here with no information other than he is thinking about another sizer.

[Petander]

Yes,even .0005 can make a difference.

My 45-70 Marlin has a sweet spot at .4595. One 9mm pistol shoots .356 all over the place while .357 is better but .358 gives the best accuracy. The barrel is 356 so 357 should work but I'll eventually try .3575.

Then there's the other important task finding the appropriate expander size/setting.

Anyway .001 is a lot and often makes a difference.

[6bg6ga]

I draw the line at .001 I'm not going to worry about a 1/2 a thousandth.

[GhostHawk]

I have "flat nosed" .30 caliber 160 gr gas checked cast for a lever action Win 94.

I drilled a hole in a plastic block just a smidge bigger than the .30 cal bullet so it would drop in freely. Then reversed the drill so the flat end is down. Set the whole assembly on a thin piece of steel and used the drill press (motor off) to flatten the point.

Compressed those bullets from .310ish out to .318 or .320.
Lubed, ran them through a Lee sizer in .311 and I had good flat nosed bullets to load.

The bullets do have to be pushed out of the load block. And I added a 3' chunk of 3/4 pvc to one of the arms of the press to give me more leverage with less work.

BTW none of the above even touched the lube grooves or gas checks.

Some of those got run through a .314 sizer for the mosin. 185 gr, large meplat, fills the chamber, hits with the wrath of god. Whats not to like.

Just sit down and figure it out. You can do this stuff. Lead is essentially like putty. Apply pressure and it will shift.-

[kungfustyle]

If you powder coat the smaller boolit, it will add .001 to .002 to the diameter. You could also get a Lee sizer die and hone it out to whatever dimension you need. As for the original question, if your bbl is .358, you will need to get your boolits to .359. Powder coat is an easy way to do that.

[lotech]

It can make a measureable difference. I used to run all .38 Special bullets (H&G #51 160 gr. SWC) through a .358" die. I don't do powder coating, just conventional lubing with a SAECO sizer / lubricator. I started using a .357" die and have seen a slight increase in accuracy in S&W revolvers and a greater accuracy increase with Colts, but they often have very tight barrels anyway. It's necessary to experiment with this.

[RED BEAR]

In a nut shell heck yes it can my 444 accuracy goes to heck with just .001 . Like i used to say when working you can drive a truck through .001 of an inch.

[Bigslug]

Yes .001" can make the difference between a happy and sad firearm.

.35 and .45 caliber. . .when you consider the sheer volume of firearms out there in those general caliber ranges, there's solid logic to just biting the weenie and laying in the entire range of sizing dies that are even in the parking lot of the ballpark. By the time you consider the nominal handgun diameters, the nominal rifle diameters, the range of variation, oddities of chamber and throat, and what a given alloy might want, you wake up one morning and realize that you can open your die box go from .448 to .462 without skipping a thousandth.

I'd certainly want to cover from .354 to .360 in that manner. Maybe even to .364 if the .38 S&W is a possibility.

Sizing dies are kind of like a wrench set - if the set is missing the correct wrench for the job, you end up doing all kinds of stupid, ill-advised things to turn the bolt.

[MostlyLeverGuns]

I have used a vise (smooth jaws) to compress a few bullets to try a fatter bullet. After a few you can get a uniform result. After size is determined, the 'right' sizer or a fatter mold can be acquired.

[Larry Gibson]

What gun/cartridge are we talking about?

Need this info to answer the question. Otherwise it's just speculation........

[Wayne Smith]

In my S&W 27 and 28 I tried .359 and it took a hard push to get them to chamber. .358 it is and they shoot fine.

[mdi]

One thousandth can make a difference, depending on whether it is plus .001" or minus .001" and where the .001" is. If I'm guessing correctly the OP is talking about 38 Special or 357 Magnum bullets and depending on the cylinder throats' diameter, prolly no difference on the target...

[sureYnot]

Just came back from the range. Tested the first rounds in my rifle after having sanded out my sizing die another .001. Group size was cut in half.
Had the same experience with a 9mm going from .357 to .358.
YMMV.

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[gnostic]

I'd take some emery cloth and polish away if I was convinced a larger bullet would be a benefit. None of my .357's will chamber a .361 bullet and unfortunately that's the size my bullets fall from the mold at....

[abunaitoo]

If you powder coat the smaller boolit, it will add .001 to .002 to the diameter. You could also get a Lee sizer die and hone it out to whatever dimension you need. As for the original question, if your bbl is .358, you will need to get your boolits to .359. Powder coat is an easy way to do that.

Now why didn't I think of that.
Getting old.
Thanks

[abunaitoo]

This is for the Destroyer rifle I'm playing with.
.358 is working, but I'm thinking it's a little small.
Bore slugged at .357.

[Conditor22]

You can either cast the chamber or try it to see if it fits.

Your PC may add more than .001. Choose the thinnest coating PC you have

[Tom_in_AZ]

Short asnwer: .358 vs .359 can make a big difference in accuracy and leading/no leading. But it’s heavily dependent on the individual gun. Slug the bore and go .001 over to start.


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[bmortell]

you can lap the sizer bigger much faster and cheaper than getting a new one. just would need a rod a drill and wrap sandpaper around it. just go slow and slug after each bit and end with 1k grit paper. id go .0005 at a time for testing bigger diameters cause you cant make it smaller again

[00buck]

This is some fun stuff

I need to get my bench back up

[megasupermagnum]

I'm in the .001" boat. Life is too short to worry about half a thou. .359" is the right fit in most 357's I've seen. Here is an example, a Dan Wesson I've been messing with in 357 maximum. It has .360" throats, and a .3576" groove. A .360" pin gauge is a loose fit in the throats, but a .361" pin gauge is too tight. .358" cast bullets lead a little, and don't shoot too well. .359" bullets shoot great, .360" bullets shoot great, unsized .361" bullets shoot great. I assume if you go big enough, accuracy would start to degrade again, as they get deformed by the throat, if they chamber at all. If the sizing is close, they come out of throats bumped up to that size.

[Tom W.]

My Ruger LC9S Pro will shoot .358 boolits, but my CZ 75 SP-01 won't. At least not without a fight. But it will shoot .357 boolits all day long.

[JonB_in_Glencoe]

This is for the Destroyer rifle I'm playing with.
.358 is working, but I'm thinking it's a little small.
Bore slugged at .357.

I think you'll be fine with 358 in that rifle.
but, if the rifle tells you it prefers a bit larger, then it's time to order the 359

[mdi]

An aside and worth nuttin'; I am a lifelong machinist/mechanic and cringe every time someone says use sand paper to work on metal. NO! Sand paper is for use on wood, plastics, or other soft material. For use on metal use emery cloth or aluminum oxide cloth (cloth is preferred over paper). Using "sand paper" on metal is like using a claw hammer on a punch or chisel...

Yep, a crotchity old mechanic...

[Petander]

I just polished a Lee .452 die today. They can be rough.

Coarsest cloth was 800 grit,then car wax, it still grew in diameter up to .4523.

Where I live,we talk metric. "One thou" in inches in 2,5 times our common "one hundredth".

[Larry Gibson]

.357, .358 or .359 ........ makes no difference to my destroyer as it's not a match rifle ....... they all shoot the same.....

[Petander]

.357, .358 or .359 ........ makes no difference to my destroyer as it's not a match rifle ....... they all shoot the same.....

I like this. You actually tried them all so you know. I do the same.

I find the "Size Hunt" very rewarding.

[Gatch]

An aside and worth nuttin'; I am a lifelong machinist/mechanic and cringe every time someone says use sand paper to work on metal. NO! Sand paper is for use on wood, plastics, or other soft material. For use on metal use emery cloth or aluminum oxide cloth (cloth is preferred over paper). Using "sand paper" on metal is like using a claw hammer on a punch or chisel...

Yep, a crotchity old mechanic...

I'm not offended or angered by much, but I nearly shed a tear when I saw an "experienced fitter/machinist" using sand paper to polish a new pump shaft at work.

"If you're going to use that ****, I'll make it out of wood next time".

SOB had no idea what I was talking about :(

[DougGuy]

.001" does make a difference. I find .001" gage pins too coarse to use for cylinder and barrel work. A reamer pilot that is .001" smaller than the hole you are reaming is not a very good fit, and not a very good guide to keep the new cut concentric with the center of the old hole. Same goes for throating an auto pistol barrel. You need half thou pins, and half thou pilots to insure you are centered.

Boolits matter less since all but the hardest castings will take on the diameter of the freebore or the cylinder throat when fired so you have this fitment thing going on that a machinist couldn't fit any tighter. I think it's a mistake to assume that oversize boolits detract from accuracy. I shoot 454190 with SPG lube, cast in 50/50+2% sized to .456" into a .451" bore that is very accurate.

[243winxb]

This is for the Destroyer rifle I'm playing with.
.358 is working, but I'm thinking it's a little small.
Bore slugged at .357.

Go harder not bigger. Add linotype.

[6bg6ga]

This is a thread that shouldn't have been started in the first place. Proper fit is key to keep from leading. If its leading and the velocity is within accepted limits then its an easy answer...increase diameter for proper fit. Not everything is answered by using a harder bullet alloy and I guess experience is a key factor here.

[Lloyd Smale]

yes it can at least in many cases.

[Drew P]

Hitek goes on much thinner. You can easily achieve diameter increases of under 1/2 mil, even less. Of course, it would be easier to hone out a sizing die to whatever you need instead of a total process change, but gosh, switching to HT coating is beneficial in MANY more ways than being able to play with diameter builds. YMMV

[sw282]

Ever watched those bobsleds bouncing off the course walls during the 0lympics?? That's the way cast boolits look when fired thru oversize cylinder throats.. Make those boolits SQUEEZE thru the throats. Not bouncing the walls like a bobsled. l'm working with a S&W 44 mag silhouette Model 29 trying to make it shoot better.. Jktd .429, .430, and .431 boolits drop thru those BIG throats.. Found a used .432'' Lee boolit sizer on GunBroken. Awaiting its arrival any day.. We will see how some 432 boolits shoot

[skeet1]

.001" is probably not a big deal except when it's .001" to small!

[cwlongshot]

I use allot of 35’s. I keep .355, .356, .357, .358, .359, .360 & .361 sizers on hand. I always run and find best to accuracy with the largest slug that will chamber.

This can change a little with higher vel rifle rounds, but this also likely has some to do with the fact that these are also a harder bullet.

Im playing with 356/357&358 now in the 350 Legend.

CW

[Petander]

I use allot of 35’s. I keep .355, .356, .357, .358, .359, .360 & .361 sizers on hand. I always run and find best to accuracy with the largest slug that will chamber.


This has been my experience with a few 9mm carbines,too. I cast heavy boolits and load subsonic.

Also,harder boolits generally come out larger than soft ones ,using the same sizer.

[cwlongshot]

.100" is probably not a big deal except when it's .100" to small!

:o:o. Im sure you knew, but .100 IS ALLOT!! .001 is a thousandths of an inch is what the question was about.

[sw282]

:o:o. Im sure you knew, but .100 IS ALLOT!! .001 is a thousandths of an inch is what the question was about.

+1+1+1

[Ramson222]

My process is to slug the barrel then start at .001 over if alloy is hard. If its a soft alloy I start at .002 over. most of the time I am only off by about +.001 if nether of the 2 starting diameters work. I powder coat everything diameters are after coating. recently I have been shooting 12bhn in rifle and handgun up to 1700fps .002 has worked out just fine with no leading.