Size for 45 ACP,,,,,,,.451 or .452

[44 WCF]

I have always sized bullets with .452 die for use in 45 ACP, but friends are telling me no no,,,,I tried both for accuracy and it's 6's.....what does anyone else use....anyone with input and experience would be apppreciated.

44 WCF

[bowenrd]

.452 for ACP and Colt

[NHlever]

I use .452 for both my 45 Colts, and my 45 ACP's. Works well for me.

[mpmarty]

Keep an open mind, folks will fill it with trash.
45acp = .452 bore = .4535 - .4540 boolits.
Bigger the better. If it will chamber it is small enough to shoot.

[bobthenailer]

ive owned at least 10 different 45 acp handguns , 5 have match barrels all shot excellent with bullets sized to 0.452 testing done from a ransom rest .
although not the same cartardge i also size 0.452 for the 454 casull

[44 WCF]

Sounds good, will stick with .452

[fredj338]

I have always sized or bought 0.452" bullets & they have given me ridiculous accuracy. I see no reason to change.

[BD]

I know I'm the minority opinion here, but I'm willing to be the odd man out. Size to your groove diameter, or .005 over, and IMHO you'll get the same accuracy with more rounds between needing to clean, and no leading. I've been preaching this for a while now, and in every Kimber and recent SA 1911 I've experienced to date .451 worked better. The colts I've slugged all went over .4505 so .452 might be better for them.
BD

[MtGun44]

No valid answer from afar. Mr. Target will give the ONLY answer that matters. Try .451,
.452 and .453. Shoot a few 10 shot groups from a stable, rested position and you will
have THE answer, regardless of what any of us say here.

Bill

[Larry Gibson]

Bigger is not always "better". For 40+ years I have sized all my cast bullets at .452" and loaded them in all sorts of makes of cases and they fed slicker than snot through every barrel I ever used them in, even with several "match" M1911s. However, I have recently (last 2 years) come up against and Kimber and 3 Para Ordnance M1911s with "match" chambers that would not take them in numerous brands of cases. Size the bullets .451" and they do fine with only a couple instances of some makes still not working. The problem is the chambers are to tight to accept many of the the loaded cartridges when the bullets are sized at .452.

And yes the case mouth flare was closed with a taper crimp die. I had loaded 500+ rounds using the Lee452-190-SWC over 5 gr of Bullseye on my Dillon SDB. That load has purred like a kitten through my Commander and my Colt IPSC M1911 with a Wilson Match barrel for 20+ years. It also has purred like a kitten through numerous other .45 ACP of various makes and even a couple subguns. Not the Para's and not the Kimber....one or two rounds per mag failed to chamber fully. When the cartridge was extracted you could readily see the burnishing on the bullet diameter of the case.

I really wanted to shoot those 500+ rounds through my P-14 so I popped the decapping rod out of a 6.5x55 FLS and the adjusting it so it sized the case/bullet portion down to where the offending cartridges chambered. I then ran all 500+ rounds through the sizer and all fed just fine. Loaded another hundred with the bullets sized .451 and they functioned fine. Never noticed any difference in accuracy and there was no leading.

Obvious to me that some guns, those with tight spec "match" chambers probably need .451 sized bullets.

Larry Gibson

[casterofboolits]

452, has worked in over a dozen 1911's for me.

[*Paladin*]

My Les Baer has a tight match chamber and it has no problems with my cast boolits. I size all of my .45 Colt and .45 ACP boolits to .452...

[btroj]

Like Bill and Larry said, your fun will tell you what it wants. Mine will feed .452 and they shoot well so I stick with that size.
Also check and see Wang your bullets actually measure. Just because your sizer says it is .452 doesn't mean that is what you will really end up with.

[pipehand]

What BD said re: Kimbers. Wasn't an accuracy issue with the three that live at our house, but the boolits sized at .451 are more reliable than those sized larger. The Smith 625 likes 'em larger, so the1911s get a H&G 68 copy, and the wheelgun gets a RN 230 at .4525.

[gray wolf]

I size .453 for my SA 1911-A1 and for a friend's Kimber custom carry.
!0,000 rounds last summer for the two guns and all is fine.
I seat and crimp in two steps, No FCD is used.
For someone to make a blanket statement and say one is better over the other I think is wrong. It has been said here a 1,000 time, slug the barrel and go one or two thou. over.
.452 works for most 45 ACP pistols with lead bullets. But common sense will tell you if you need
a little adjustment because of you individual pistol.

[Jailer]

My Glock 21 barrel liked .453 best, but the KKM barrel I just got won't chamber them. It all depends on what the gun will run.

[Catshooter]

My two S&Ws have bores that are .4518, each. So a .452 will lead some. A .453 leads zero.


Cat

[captaint]

What Paladin said - plus one. Noticed that my .452 sizer does make them more like .4517. They all work fine though. enjoy Mike

[oscarflytyer]

OK - I am a bit confused here... Don't see anyone suggesting slugging the bore!

I slugged my bore. Came out to .451". So I followed the suggested wisdom and size all my bullets .001" over - to .452".

Shoots them like a laser beam - after a small bit of accurizing - replacement bbl bushing and .005" oversized bbl link and pin. Did and does shoot them better than factory hardball prior to the accurizing as well.

[randyrat]

Bigger is not always "better". For 40+ years I have sized all my cast bullets at .452" and loaded them in all sorts of makes of cases and they fed slicker than snot through every barrel I ever used them in, even with several "match" M1911s. However, I have recently (last 2 years) come up against and Kimber and 3 Para Ordnance M1911s with "match" chambers that would not take them in numerous brands of cases. Size the bullets .451" and they do fine with only a couple instances of some makes still not working. The problem is the chambers are to tight to accept many of the the loaded cartridges when the bullets are sized at .452.

And yes the case mouth flare was closed with a taper crimp die. I had loaded 500+ rounds using the Lee452-190-SWC over 5 gr of Bullseye on my Dillon SDB. That load has purred like a kitten through my Commander and my Colt IPSC M1911 with a Wilson Match barrel for 20+ years. It also has purred like a kitten through numerous other .45 ACP of various makes and even a couple subguns. Not the Para's and not the Kimber....one or two rounds per mag failed to chamber fully. When the cartridge was extracted you could readily see the burnishing on the bullet diameter of the case.

I really wanted to shoot those 500+ rounds through my P-14 so I popped the decapping rod out of a 6.5x55 FLS and the adjusting it so it sized the case/bullet portion down to where the offending cartridges chambered. I then ran all 500+ rounds through the sizer and all fed just fine. Loaded another hundred with the bullets sized .451 and they functioned fine. Never noticed any difference in accuracy and there was no leading.

Obvious to me that some guns, those with tight spec "match" chambers probably need .451 sized bullets.

Larry Gibson Ditto,,,,,,,,,, only I could not have said it better...There are a few 1911s that need a .451 to chamber

[Johnw...ski]

I have always sized mine at .451 but last year I didn't want to take the time to cast so I bought some flat base boolits that were only offered sized at .452.
I got 2000 of them and figured I would try a box before loading them all. I am not the greatest shot but can keep them in the black on a standard 50 foot indoor target, the groups with these new boolits were as tight as before from right to left but would use all of the black and then some vertically. Thinking I may have been having a bad day I tried shooting from a rest, slightly better but still the same verticle group. I went home and sized another box to .451, loaded them and went back to the range. Apart from a very few fliers that I can honestly say were me my groups were consistantly circular and in the black either shooting one handed or from a rest.

I know .452 seems to be the go to size for 1911's if not bigger but I have always had good luck with my Gold Cup or Smith Mod. 25 sizing at .451. A friend who was at the time the national pistol champ gave me the advise to size to .451 when I got my first 1911. For me it was good advise.

John

[Bret4207]

OK - I am a bit confused here... Don't see anyone suggesting slugging the bore!

I slugged my bore. Came out to .451". So I followed the suggested wisdom and size all my bullets .001" over - to .452".

Shoots them like a laser beam - after a small bit of accurizing - replacement bbl bushing and .005" oversized bbl link and pin. Did and does shoot them better than factory hardball prior to the accurizing as well.

Slugging gives you a place to start, but that's all it does. Every barrel and load will give different dynamic fit. I'd follow Mtngn44's advice and try the target for a final determination.

[BD]

In 1911 barrels there's another factor involved, particularly when using SWC designs, and that's the diameter of the chamber at the mouth of the throat, (if there is a throat). You cannot take a .452 or .453 boolit with a square edge front drive band and force it through a .451 hole, also with a square edge, without disrupting that front drive band and/or shaving some lead. That disruption has an effect, and any lead shaved winds up someplace.

In my own experience, I've found that sizing to the diameter of the throat and seating out long enough that the boolit can center in the bore is beneficial to accuracy, and avoids the common leading in the first inch or two of the barrel. As with most guns, it's the throat that I size to, not the barrel.

1911 barrels were typically throated by hand, using a seperate reamer. These days, who knows? I've seen many examples of Kimbers which had little if any throat, leaving the lands with a square edge and the chamber mouth at .4505 or so, and I've seen Colts in which the guy with the throating reamer was a little too enthusiastic resulting in a nice smooth approach to the lands, but a chamber mouth of .452 or more which may or may not still be precisely round. Every barrel is an individual in this respect and YMMV.

BD

[358wcf]

Gents,
I've been exclusively a S&W revolver man for almost 40 years, and loved it. The absolute reliability and phenomenal accuracy made me stay that way- Why change?
Last year, at the insistence of both Son-in-Laws, who shoot autos exclusively, I agreed to try an auto.
As a traditionalist, it had to be a 45cal 1911. At my age, I'm through playing with low-end guns and upgrading them as I go (that's a false economy, in my book)- today, I buy them just the way I want them, or wait til I can afford to get just the model I want, equipped the way I want.
First 1911 purchase last fall was a new Kimber Eclipse Target 5", followed shortly by an Ed Brown Executive Target 5". I feed both a bullseye load of 200gr SWC cast over 4.0gr Bullseye on a WLP primer, in fully conditioned brass, FL resized and taper crimped. Boolits are sized and lubed w/BAC to .452".
I am astounded by the 100% reliability (no jams, FTF, or stovepipes at all!), and the accuracy is amazing to me. One large, ragged hole at 15yds, and about a 2.5" group at 25yds- much, much better than I ever expected. Today's high-end target pistols shoot much better than I can hold, for sure.
With these results using .452" boolits, at about 500 rounds through each pistol without failure, I have no reason at all to even try going to .451.
Oh, by the way, I've always sized my 45 AutoRim (S&W Model 25) to .452 as well, and all it shoots is X's, every day!
I've no reason to change, just now. Perhaps I'll test some .451's this summer in all and be certain--

Chuck
358wcf

[Skipper488]

I know I need to slug my barrel but lacking the tools or a gun shop nearby that does it I went with "the classic" wisdom and ordered a .452 mold, casting with wheel weights it drops .4525 I shoot as cast tumble lubed. They work great.

[Bret4207]

I know I need to slug my barrel but lacking the tools or a gun shop nearby that does it I went with "the classic" wisdom and ordered a .452 mold, casting with wheel weights it drops .4525 I shoot as cast tumble lubed. They work great.

There are a few of us here who are of the mind that slugging is something to one when a problem crops up rather than a chore to be done to every gun. I've slugged maybe 4 or 5 of my 60+ guns. IOW, if you stumble on something that works, why mess with it?

[9.3X62AL]

I've slugged about half of the barrels and throats of the rifles and handguns in my eclectic collection. Specific to 45 ACP, I've had decent results running boolits at .452" in about a dozen pistols. In the most recent 45 ACP venture--Glock 21 flavor--.452" and .454" sizing with 3 differing boolits didn't make a whit of difference in accuracy or leading potential.

With my 45 Colt throats honed to .453", .454" boolits do well being directed into .452" grooves.

[Bass Ackward]

I find that "size" .... is not a blanket variable. It can also be dependent and vary with design, lube, and hardness.

I slug everything. And I slug every so often because the gun can clean up and alter dimensions.

But as I always state, I let the gun tell me where the diameter should be.

[Dale53]

I let the gun tell me where the diameter should be.

True wisdom, there, Bass. True wisdom!

All of that said, all of my .45's (several 1911's, a couple of 625's in .45 ACP, and a couple of Ruger Single Actions) operate perfectly and accurately with .452". I have sized my throats, this was NOT done blindly.

Even my stock Kimber CDP II Ultra works just fine with .452". Just lucky, I guess...

Dale53

[Cherokee]

If 452 has worked great for you, ignore your well-meaning friends. I use 452 in all my 45 ACP's.

[USSR]

My tight chambered Series 70 Gold Cup, just plain don't like to chamber .452" bullets. I switched to a .451" sizing die and all is well.

Don

[44 WCF]

Thank you everyone for all the input. Has been great.

[Larry Gibson]

Slugging the barrel doesn't matter much if the chamber won't allow larger than a .451" diameter bullet. There are other variables and considerations than throat size and groove depth. I was blissfully happy for 40+ years sizing my .45 bullets at .452. Then I recently ran onto and now own one that won't take .452 sized bullets. Just the way it goes.

Larry Gibson

[randyrat]

Yep, I had a Para GI Expert..I tried .452 then after 2-3%% FTFs I asked a friend of mine...He said; He used .451 for years in his Gold Cup. So I tried Factory Crimp die, It worked but ruined the accuracy. So I went with a .451 reluctantly, it worked!
Here are your options....
Thin brass use.452
Regular brass... may be able to use use .452
Open your throat up (Mo money and possibly ruin a tight chambered gun)
Use a Factory Crimp die- possibly ruin your accuracy, leading
Or just size your boolits to .451 or .4515
Trade barrels

[Char-Gar]

If the memory chip in my head hasn't failed totaly, I started casting for the 45 ACP in 1961 and used a .452 die in the old Lyman 45. I cast and sized probably 250K rounds .452. The rounds were shot through a about a dozen 1911 pistols. About 20 years ago, I bought a .451 die to see it worked any better. It didn't! So, I went back to .452 and see no reason to change.

I have used many types of brass both GI and commercial. I use a proper taper crimp. I have found the 45 ACP round very easy to load with cast bullets for reliability and accuracy in the 1911 pistols. I read posts like this about folks problems, but I have never experienced them. If the rounds was so persnickity and difficult to load, I think I would have seen that by now.

[cajun shooter]

First let me say that this thread has some good and bad information. Most people don't realize how sizing dies are made. A die that is stamped .452 is most of the time .4515. A die that is stamped .454 is .4535; ask Lathesmith how he finishes his dies. If you have a set of pin gauges measure your die and see what it tells you. The question of what do you use in your guns is one that should never be asked. Even guns coming off the same work day together are not the same. Certain Brands of guns do things different from other brands. Ruger is well known for tight chambers and bores. In a revolver the size of the bore should take a back seat to the size of each chamber in that cylinder. Over the years even the best companies made bad guns. Colt had a spell where the cylinders were way over bore size and not much use except as a wall hanger. The first thing to do with the auto's is to look at the depth of your rifling in your barrel. Some are so shallow that you need to be firing a larger bullet than the most recommended size of .451 and the post about SWC is true. A more cowboy style of bullet which is RNFP will feed in most all guns. Think cylinder when trying to make a revolver shoot better. Your findings may shock or please you.

[LUCKYDAWG13]

were do you get a ..453 sizeing die ?

[plainsman456]

So far I have shot 452 dia. boolits in my Colt,but I have a 451 die to try out just to see if there is any difference.

[NHlever]

Every time we think we have a "rule" something comes along to disprove it. I have two .357 magnum revolvers (happen to be Rugers) that have throats that are a tight .358 diameter, and surprisingly consistant. One day on a whim I loaded some boolits that were sized .357, and they shot noticably better, and leaded less than the .358 diameter boolits I had been shooting for a few years. Never hurts to try what you have at least, and just listen to the gun as others have said.

[felix]

Yes, that is still the rule. However, the rule MUST be understood. The diameter of the boolit the gun SEES during ignition is the diameter desired. Question remains WHERE does the gun like that diameter, and WHEN is that diameter within the acceleration curve? After that is thoroughly known, then the hardness of the boolit can be optimized. These questions are answered during the experimentation exercises. ... felix

[btroj]

Ah yes, the balance between the pressure curve, diameter, and hardness.
There is the answer.

Now how to find that quickly, that is the problem. Like Fekix said, experimentation is the key.

I like how Felix can say so much with so few words.

[Char-Gar]

Luckydawg.... I got a .453 die by buying a Lyman .452 die. Quit often a store bought size die will deliver something different from what is it marked. There is machine tolerances and bullet "spring back" that is different with various alloys.

I went through three store bought .313 dies before I gave up and had buckshot make me one that really sized my bullets .313.

[Jailer]

Slugging the barrel doesn't matter much if the chamber won't allow larger than a .451" diameter bullet. There are other variables and considerations than throat size and groove depth. I was blissfully happy for 40+ years sizing my .45 bullets at .452. Then I recently ran onto and now own one that won't take .452 sized bullets. Just the way it goes.

Larry Gibson

I'm running into this with the KKM barrel I just got for my Glock 21. The base of the boolits in the case is preventing the rounds from chambering completely. They also have to be seated deeper than they did in the stock barrel. I'm going to try some at .451 and see if they will shoot accurately without leading badly.

[Jailer]

Well I shot some sized at .451 today. Only 75 rounds total through it so far at that size but I have zero leading. None.

Boolit was Lee 452-230 TC sized to .451 OAL of 1.178 with 5gr of W231. Too bad it took me over 700 rounds to figure that out. [smilie=b: