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Pop_No_Kick
07-03-2005, 03:05 AM
Next thing I need to Learn is How to check and verify the Headspace
on a Non Mil. Colt .45 ACP. (Good Shooter -storeBoughts-)

Also I would think that the headspace is how the bullet is seated?
I need to get this Lack of knowlage issue behind me So I
can Start To Cast:

Mould I have is a 90346 - 452-190 SWC With Sizer .451 #82232

Any Help will Be Appreciated


Thanx's
Chuck

Frank46
07-03-2005, 04:17 AM
Chuck, here's what I do for my springfield 1911. Seac bullet out so it will not allso gun to go into battery. Screw down the bullet seating screw about 1/4 turn seat bullet slightly deaper. Check to see if slide will fully close. If not repeat with bullet seating die and screw. As an after check bull bbl out and see if base of cartridge is even with the hood of the bbl. If it is then your home free. To far out reduce the amount by seating bullet deaper. When I first started reloading 45acp thats what was explained to me. Gun has over 5k rounds throuh it and not one bobble yet. Frank

Buckshot
07-03-2005, 05:47 AM
.............What Frank said. I don't think there is a 45ACP case made that will properly headspace on the casemouth in a correct chamber. Usually the extractor has ahold of the rim to hold it back against the firing pin's strike. That and the fact that the case is kinda wedged against the side of the chamber.

Many years ago I'd read an article by Dean Grennell where he suggested letting the slug do the headspacing. Seat it out to engrave and stop the loaded round. Of course you have OAL issues to be able to fit and feed from the magazine.

Kind of on the subject, one of my old shooting buddies decided to do a test. He bought 100 rounds of Winchester 45 mag brass and shortened it to his Kimber's exact chamber length. It truly would headspace on the casemouth. Then he used 100 of his regular 45 ACP cases (headstamp immaterial). All of them were loaded with a known accuracy load from previous work. There was no practical difference in accuracy between the 2 batches.

...............Buckshot

Willbird
07-03-2005, 07:55 AM
I learned from the gunsmith that built my 1911 pistol that one can directly measure the depth of a chamber in many pistol bbls with dial calipers, just measure from the hood down to the headspace shoulder.

All things considered I know from direct experience that a well (and I mean WELL) done 1911 will put 5 cast bullets into 1-1/4" at 50 yards from a ransom rest. The gunsmith that built the gun didnt know that could be done with cast.

and that wasnt headspacing on the bullet either, 4.0 of bullseye and federal cases, and the 452460 bullet that some think is not accurate. My pistol has a Clark bbl and is fit quite tight slide to frame, but is 100% reliable.

Bill

StarMetal
07-03-2005, 10:57 AM
Do you know that your car engine is suppose to be built to correct measurement specifications? When you build an engine and you do in the engine building circles what is called "Blueprinting" your engine, that is exactly what you are doing. Building it to measurement specifications. For example if the ring end gaps are suppose to be .018 inch, you make sure each ring in itps perspective cylinder measures that. Same for main crank bearing clearances. If they are suppose to be .002 or .003 inch, you make sure they are. Point is I sincerely doubt that many engines on the road are perfectly blueprinted.

What's the point of all this? You fellows get way too deep in this gun stuff. On the 45acp 1911 as long as the headspace isn't dangerously large, just load the damn things so the gun functions properly. Now headspace on a rifle is a whole different ballgame.

Joe

Willbird
07-03-2005, 11:22 AM
Even mixed brass doesnt matter to 45 acp with target type loadings from what I have seen of work done by some good pistolsmiths in a ransom rest, it must be the most forgiving ctg. of them all. I would avoid mixing in R-P brass which is notorious for being smaller (thinner necks) and ball mil brass.

at bullseye target velocity bullet quality is the biggest factor in 45 acp accuracy in a properly accurised pistol IMHO.

and sub 1" groups at 25 yards means it is time to work on the shooter not the gun.

as to seating the bullets, I was taught to leave .03" of the first band sticking out, there is some room to tune so that your gun works nicely there, and to taper crimp to .470" dia at the case mouth (this helps feeding too).

otherwise avoid powders that dump unburnt granules into the locking lugs (bullseye was the cleanest, now it seems clays is....231 is NOT by far at bullseye velocities)

Bill

StarMetal
07-03-2005, 11:37 AM
Bill

I too load my 45acp to have 1/32 of an inch protruding from the case mouth, which is .03125. I've never had any problems with it. I don't understand why someone wanting to load for this round just doesn't read the reloading book on loading the 45 acp, assemble the componants just as the book describes and goes from there. They give an over all cartridge lenght. If you're loading a bullet that's not the one in the manual pick a bullet that is closest in form to the one you have or try a different brand reloading manual. Most important thing when you do this is to make sure the weight of the bullet is the same as the one in the manual as to not raise pressures. That is don't substitute a 230 gr bullet for a max load using a 185 in the book. Anyways you just go out and try it then and see how it functions and shoot and go from there.

Joe

Willbird
07-03-2005, 11:54 AM
I was working with 1/32 for years StarMetal, but having to calibrate for temperature to hold the required .0005" tolerance called for in a 4 place decimal got to be a royal pain in the ass.

Now dropping to two place decimals I'm sure has increased group size a few .001" but it is within allowed deviation.


Bill

StarMetal
07-03-2005, 12:18 PM
Bill

that's just my general starting point.

Joe

David R
07-03-2005, 01:52 PM
As far as I am concerened, 45 auto headspaces on the boolit.

KYCaster
07-03-2005, 05:53 PM
I agree with everything Joe and Bill have said about the subject. In addition I have seen 10mm and 40S&W feed from the magazine and fired in 45cal. guns. And 9mm and 38 super feed from the magazine and fired in 40S&W guns. This would not be possible if the cartridge headspaced on the case mouth or on the bullet since the sub cal. cartridge will slide completely through the larger barrel. The extractor will hold the case tight enough to get reliable ignition.
It's kinda scarey, being around people who do that kind of thing on a regular basis.

Jerry

floodgate
07-03-2005, 08:37 PM
It is a KNOWN FACK that the .45 ACP headspaces on the case mouth and ONLY on the case mouth! I've seen it wrote up in dozens of books and manuals

Of course, it is also a KNOWN FACK that the bumblebee can't fly!

(It's been a l o n g day!)

floodgate

arkypete
07-03-2005, 10:24 PM
I'll run my 215 grain, 220 grain and 200 grain bullets thru my .454 sizer die just to lube the bullets. Sometimes I actually size them thru the .452 die but that's a rarity since I shoot more 45 Colt bullets. When I seat the bullet in the case and apply the taper crimp I get all the sizing I need.
I use a length that works thru the magazine, I use Colt magazines, I've found them to allow a longer cartridge, but I only compared them against some of the surplus stuff, 20 years ago.
For making sure that the cartridge will feed thru the gun I'll drop a cartridge down into the chamber of the barrel. The pistol is field stripped. As long as the case head does not stick to far out beyond the hood or drop too far into the chamber, the ammo works. I do it all be feel and comparison. Got used to doing that, prior to owning a vernier caliper.
This was my system back when I was shooting bullseye, and of course the press remained set up for years, without changing the powder measure or die settings.
Jim

old gunner
07-04-2005, 08:18 PM
The 45 acp does headspace on the mouth of the case, You may use the boolit if it has a sharp shoulder such as a wad cutter. What works very well for Me is to use the barrel, unless a guage is available. Merely drop the loader round in the barrel, shoul stop at the right place. Test this metod with a loaded factory round if You are not sure about what it should look like.
Use a taper crimp die, so the mouth of the case is not shortened during the crimping stage.
Bill

StarMetal
07-04-2005, 08:24 PM
You don't have to use a taper crimp on the 45 acp. You can use a roll crimp, up to .020's of a roll crimp in fact. Mr Harris of the NRA did an extensive test of target 45acp load using a very heavy bench fixture which was a rifle action with a short very heavy barrel to eliminate any human error in firing and his test conclusively proved the roll crimp out shot the taper crimp. He did this for the full wadcutter in the 38 special too. You don't have to have a sharp shoulder for a 45 acp lead bullet to space off the bullet as the 45 acp barrel doesn't have a throat in it like a rifle. The rifling is damn near the mouth of case, the bullet hits this. Think about it, in order for a bullet shoulder to hit the shoulder that the case is suppose to hit on, it would have to be the same diameter as the outside of the case...and that's just going to happen.

Joe

Pop_No_Kick
07-04-2005, 10:14 PM
You don't have to use a taper crimp on the 45 acp. You can use a roll crimp, up to .020's of a roll crimp in fact. Mr Harris of the NRA did an extensive test of target 45acp load using a very heavy bench fixture which was a rifle action with a short very heavy barrel to eliminate any human error in firing and his test conclusively proved the roll crimp out shot the taper crimp. He did this for the full wadcutter in the 38 special too. You don't have to have a sharp shoulder for a 45 acp lead bullet to space off the bullet as the 45 acp barrel doesn't have a throat in it like a rifle. The rifling is damn near the mouth of case, the bullet hits this. Think about it, in order for a bullet shoulder to hit the shoulder that the case is suppose to hit on, it would have to be the same diameter as the outside of the case...and that's just going to happen.

Joe
Roll Crimp ?
Uh. first time i heard of this? Is this in some die's or is this another piece of hardware?

" I Don't Have To Be Smart, Just Keep Smart People Around Me! "

Thanx's
Chuck

StarMetal
07-04-2005, 10:27 PM
Come on Chuck...you're kidding me right? Most dies (not all) have a ledge inside the seater that will turn the neck of a case inward, called "roll crimping". For starters all the case lenghts have to be exactly the same, so that means you have to trim them to an exact lenght. Second the bullet should have a crimp groove and if a jacketed it should have a cannelure. The rounds will actually look more rolled crimped in revolver rounds such as 357's, 44's, 45's, etc then a jacket round in the same caliber (and especially so in rifle round) because cannelures are not especially deep. Third, if you overcrimp you can and will crumple the neck.

You can look inside your seater die and see if that ledge is there and also by reading the little manual that come with the dies as to whether they will roll crimp.

Joe

boogerred
07-04-2005, 10:50 PM
an oldtimer told me to finger seat your chosen bullet long in an unprimed, unpowderd case, lock the slide back, insert dummy round halfway, release slide until just touching dummy and let er rip. carefully eject, measure OAL,check for mag fit and adjust. he said the spring pressure would seat the bullet correctly. he also said the case couldnt be too loose or tight to allow free bullet movement(thats a touchy,feely thing youll have to touch and feel for yourself). ive done that for about 3k rounds with no bad POPS R KICKS yet

Pop_No_Kick
07-04-2005, 11:17 PM
Come on Chuck...you're kidding me right? Most dies (not all) have a ledge inside the seater that will turn the neck of a case inward, called "roll crimping". For starters all the case lenghts have to be exactly the same, so that means you have to trim them to an exact lenght. Second the bullet should have a crimp groove and if a jacketed it should have a cannelure. The rounds will actually look more rolled crimped in revolver rounds such as 357's, 44's, 45's, etc then a jacket round in the same caliber (and especially so in rifle round) because cannelures are not especially deep. Third, if you overcrimp you can and will crumple the neck.

You can look inside your seater die and see if that ledge is there and also by reading the little manual that come with the dies as to whether they will roll crimp.

Joe
I Wish I was Kidding...But I see what you were talking about
As a Newbie I just call that a basic crimp and YES all my dies (pistol) Do that
and How right you are about to much will crumple the neck..
Thanx's for clearing that up for me...It just sounded like something "new" maybe. I dint crimp my .38 spec. But I do the .357 or the recoil will unseat the Boolit under the heavy recoil.
Cool Joe. I see I not as dumb as i feel.

Thanx's
Chuck

sundog
07-05-2005, 12:01 AM
Headspace is on the taper, not case mouth, not the boolit, unless loaded long, and not the extractor. I've shot roll crimped 45 acp, and it works. Never saw a case too long, always way short. With a correct size boolit in a reasonably serviceable 1911 (and prolly alot of other actions) with a correct taper, it will headspace, even if the boolit is seated too deep. Take the barrel out and use it for a guage. If its properly tapered its entire length it will fit flush regardless of OAL (unless too long) or case length (never saw one too long). Actually the taper is a very modified shoulder. Kinda like neck sizing a rimmed magnum to change the headspace to the shoulder from the rim, sorta, but not exactly. If the taper is under or over or wrong angle, headspace is not correct. That may not be exactly correct either, because if the angle is too great but the rear end is correct it would still seat in the chamber at the correct location. My guess is that a 45 acp case length guage is nothing more than a tapered hole. Might as well just use the barrel. sundog

StarMetal
07-05-2005, 12:09 AM
That's a good point Sundog...contrary to popular belief the 45acp case is a tapered one, not a straight one. One reason I don't like titanium or carbide dies for it. I have a set of Hornady titanium coated dies and they don't size the case down enough so I use my old regular RCBS dies where I have to lube the cases. One thing I noticed about the Hornady dies is that they are marke 45acp, 45AR, and 45LC. Now you know if they size 45 LC they can't be right for the 45acp, and you'd think that they would make them size to the smallest size, but lookes like they geared it towards the 45LC. Same with the 9mm Luger, it's tapered also.

Joe

old gunner
07-05-2005, 05:24 PM
My guage (Wilson) has a little flat groove milled across the end of the case, works just like an over size chamber. The sized and loaded case is a loose fit in the guage, unlike the fit in a chamber. When I use the guage, the case stops on a sharp shoulder in the guage. I have tested the guage by trimming the case, and head space is shortened. I never guage anymore, if the loaded round chambers, I shoot it.
By the way an old test for a worn 45acp barrel was to put a loaded round in a barrel(out of the gun) press it in the chamber with Your thumb. Release, turn the barrel upsise down and the loaded round should fall out.
Bill

KYCaster
07-05-2005, 08:58 PM
Sundog sez: "Headspace is on the taper, not case mouth, not the boolit, unless loaded long, and not the extractor."
Sundog: I've seen reference to a "tapered .45ACP" several times in the last couple of years but I have yet to see any illustration of it. Could you please point me to a site, either on the net or in print that has a properly demisioned drawing of a tapered .45ACP. I just checked all my reloading manuals and all of them show that the 9mm Luger has .011 taper but the 45 and all the other ACP family of cartridges are straight. I measured my Clymer .45 reamer and found .001 taper.(probably because it's worn somewhat) In Jerry Kuhnhausen's " The Colt .45 Automatic A Shop Manual" I found, "Measurements shorter than .898" ["go gauge"] are not always a short chamber indication. The chamber may be slightly tapered from use of a dulled finish reamer. The effect is much the same chambering is resistive. Recut these chambers carefullly with a new finish reamer. This work requires "go/no-go" headspace gauges.....With the very generous .022" longer than "go" given by the 45ACP "no-go" gauge [.920"] you might not expect larger headspaces."
This seems to imply that the "go gauge" is straight and that an improperly cut tapered chamber will cause it to stop short of the headspace shoulder of the chamber. Also, a very generous +.022 "no-go gauge" would allow such a large variation in case length (and overall length) that repeatable headspacing would be almost impossible without using Boogerred's method to tailor the OAL to the individual chamber.
Meanwhile........back to my original point, I haven't seen any evidence that John Browning designed the .45ACP with a taper. Just look at the magazines. All the mags I've seen for the .45 (and all the ACP's plus the .30 carbine) including the Thompson SMG and M3 Greasegun, have a rectangular magazine.(no taper front to back) That's because the straight cases will stack flat whereas the tapered 9mm needs a magazine narrower at the front to take up the extra space and keep the top round level.
Again, this is something that I've seen in print just recently and I'd like to see some proof to verify it so if you can show me where to find the info, please do.

Jerry
PS. Please don't take this as a personal attack. I've been trying to find info about this since I first saw it mentioned and you're one of the few who have said it that I have been able to respond to....Inquiring minds want to know.

Pop_No_Kick
07-05-2005, 09:17 PM
Come on Chuck...you're kidding me right? Most dies (not all) have a ledge inside the seater that will turn the neck of a case inward, called "roll crimping". For starters all the case lenghts have to be exactly the same, so that means you have to trim them to an exact lenght. Second the bullet should have a crimp groove and if a jacketed it should have a cannelure. The rounds will actually look more rolled crimped in revolver rounds such as 357's, 44's, 45's, etc then a jacket round in the same caliber (and especially so in rifle round) because cannelures are not especially deep. Third, if you overcrimp you can and will crumple the neck.

You can look inside your seater die and see if that ledge is there and also by reading the little manual that come with the dies as to whether they will roll crimp.

Joe

Alot of Good info and variation's on the .45ACP, but of course
for this is a popular cartr.

Starmetel, I had to Look-up this in my old reloaders Book
the "Lyman 45th Edition"

It's listed in the getting started section Pg. 154 under crimping.

QUOTE> "DO NOT CRIMP on rimless auto-loading cartridges such as 45 auto, 380 auto, 9 m/m Luger or any case that headspaces on the mouth. If a case of this type is crimped, It can shorten the overall length of the case and create an excessive headspace
condition." /end quote.

Thats Where all my Confusion is from, also I was to believe
that it head spaced on the cartidge not mouth becouse the extracter has it..

Now, I will say this before you do " I WILL GET A NEW RELOADERS MANUAL ! hehhee.

P.s. There is no mention of the term Roll Crimp, So I Will assume that this is ment as standard crimp.

Occupational "hobby" Hazzard. " You say patato & I say POTOTO"

Thanx's ya'll for your help "don't stop"
Chuck.

StarMetal
07-05-2005, 09:23 PM
Pop....I'll have to scan the write up by Mr. Harris in the NRA Cast Bullet Book and send it to you. By the way Mr. Harris said to put about a .020 of an inch roll crimp on them....think about that...it's not alot.

Yeah there was alot of stuff said on the 45acp headspacing, but it all boils down to just a few things if you condense it.

Joe

Pop_No_Kick
07-06-2005, 05:42 AM
Pop....I'll have to scan the write up by Mr. Harris in the NRA Cast Bullet Book and send it to you. By the way Mr. Harris said to put about a .020 of an inch roll crimp on them....think about that...it's not alot.

Yeah there was alot of stuff said on the 45acp headspacing, but it all boils down to just a few things if you condense it.

JoeI will aprec. that. Got My Brass Ready
and will mold in the p.m. also need to do some .357
for the revolvers.

Thanx's again.

Willbird
07-06-2005, 06:34 AM
I just re-read the portion of the book Star is talking about, the differances in group size between roll, taper, and no crimp were very subtle. almost within std. deviation, also the powder charges between the differant styles of bullets and types of crimps were not the same.

Mr. Harris did state that the most important function of the crimp was to prevent the bullet from being seated deeper while it is feeding into the chamber. This is sort of the reverse of why we use a crimp in revolvers, to prevent the recoil from moving the bullets in the other ctg. in the cyl. (and to make ignition consistant by increasing bullet pull)

Bill

sundog
07-06-2005, 09:51 AM
Jerry, not a problem. I don't have anything here in front of me to get numbers, but here's my idea. And I will not refute anything you say, because you are most prolly completely correct. My thinking is this though. Put a taper crimp on a 45 acp and the mouth is smaller than the base. If the chamber is cut straight wall then the loaded round will go in only so far and stop if the base is larger than the cartridge. Of course, I may be all fouled up in my thinking, but it's a matter of elimination. BD did an very good extensive write up a while back about how the extractor interacts. If there's a gap between the back of the extractor and the front of the rim then the extractor is not holding it -- extractor is simply extending into the recess and not pushing or pulling in either direction. I think that's how he explained it.

Here's my thoughts. If the extractor doesn't hold it, the case mouth does not hold it, the boolit does not hold.... Well just extactly what is holding it? Again, no problem with what you say. I'm enjoying batting this around. Straight wall case when sized, but tapered, at least in the forward part, after crimping.

I was at a Wild Bunch match a cupple months ago and several of us were playing 'show and tell' with our 1917s. I have a Colt and a Smith. One of the fellers told me about one of the models (don't remember which) that for awhile was bored straight thru (I can only suppose he is correct because I don't know). He said that 45 acp ammo would drop right thru the cylinder. Neither of mine will do this, I can shoot 45 acp in either without the clip, but of course they will not extract - they have to be pushed out. What's it headspacing on? I think it's the back part of the case because of the taper crimp. It's not the mouth, and not the boolit.

Anyways, if I'm all wet, no problem. It's just amazing to me that something that was developed so long ago is still in vogue. I'll keep aloadin' and ashootin' them regardless of where it headspaces. My favoritest handgun load. sundog

StarMetal
07-06-2005, 10:04 AM
Willbird

Sounds like you may taper crimp and resent roll crimps beating taper crimps. Fact is Mr. Harris's roll crimp loads beat the taper crimps. Just like quarter mile auto racing, every "little" bit of extra horsepower, every bit of "less" weight, and every bit of each "tenth" a second...MATTER!

Joe

BlueMoon
07-06-2005, 01:44 PM
Just my opinion but,
I thought you only put a crimp on a 45acp or 9mm case to take the bell off. That's what I usually do and I try not to bell any more than I have to. But some cast bullets need a bell so I put it on. My FL die for my 45acp and 9mm is what I depend on to make the bullet not set back into the case not a crimp.

I used to just take the barrel out of my 45 and use as a chamber gauge but the last time I loaded any, I was too lazy and got out my forgotten Midway gauge and found the crimp I usually put on would only let the loaded round go halfway into the gauge. It had been awhile since I had loaded up any 45acp as I have a bunch already loaded from '97 forward. So I tightened up the crimp on some to where they would go into the gauge but left most to where they would only go 1/2 to 2/3rds. I bet all of them work OK though because the 45acp seems to be pretty forgiving. And I measure across the crimp with a caliper or micrometer and get about .472"-.473"+, depending on case, I guess.

Bill

StarMetal
07-06-2005, 01:54 PM
Bluemoon

I'm trying to post the article out of the NRA book by Mr. Harris but my photo website is down. Anyways after you remove the flare,or crimp, the case mouth on a 45 acp should be .460, thus why all of them aren't going into your Midway gauge.

Joe

StarMetal
07-06-2005, 08:33 PM
Since my photo imaging site may be out of business I'm trying these images as attachments and frankly don't know what I'm doing so lets see if it works. What they are, are copies of the NRA Cast Bullet book articles on accurate 45acp loads and crimping that I told Pop I would post. Here goes:

http://castboolits.gunloads.com/attachment.php?attachmentid=169&stc=1

http://castboolits.gunloads.com/attachment.php?attachmentid=170&stc=1

StarMetal
07-06-2005, 08:34 PM
Well I got it half-ass but they are here. Read the bottom one first.

Joe

Willbird
07-06-2005, 09:23 PM
ok I have the book in front of me

bullets tested with both crimps , same alloy, and equal powder charges

H&G 130 (first series)

Roll 3.6" average 4.9" 30 shot composite
Taper 2.75" average 2.9" 30 shot composite ( best by .86 at 50yds)
none 3.6" average 4.3" 30 shot composite

H&G 130 second series

roll 2.11 average 2.45 30 shot composite (best by .1" at 50 yards)
taper 2.21 average 2.7 30 shot composite
none 2.81 average 3.5 30 shot composite

absolute smallest (2 of them H&G 130) average groups were 2.08" both with roll, one cast in type metal, one 18-1.

also .460 is way more taper crimp than most folks use. .470 is an often quoted taper crimp dia, Mr. Harris was taper and roll crimping to .453" or so by my math.

I am for sure not prejudiced against roll crimps, I use them all the time, just not in 45 acp, after reading the article however I would not be afraid to try them in 45 acp. I would not crimp that much unless some reason dictated it.

.470 taper crimp shot 1.25" for me at 50 yds


Bill

Pop_No_Kick
07-07-2005, 12:17 AM
Well I got it half-ass but they are here. Read the bottom one first.

Joe
Great Excerpt's. I see .020" ain't much of a crimp.
Well i still need to slug the bbl. and get a sizer. if it dont
match-up with the one i have.

Thanx's STARMETEL for clearing all this up. I saved the pics. to blow it up to read.

O'h you to willbird !
P.S I will let ya'll know how it works out, when its time
to see how it seats...
Chuck.

Willbird
07-07-2005, 06:44 AM
.02 is a HUGE amount of crimp with a taper crimp die, it would do terrible damage to a bullet, taper crimp dies swage the bullet smaller just from how they work, being a taper the more crimp you apply the greater the length of damaged area. Roll crimp applied to a bullet with no cannalure also causes damage but it occurs over a much shorter length.


Bill

StarMetal
07-07-2005, 10:59 AM
Willbird

.020 crimp is a roll crimp, not a crimp with a taper die. By the way a crimp is applied to the cartridge case mouth, not the bullet. I assume you used bullet in a termnology that describes the whole works. How did you come up with a taper crimp rolls crimps?

Joe

Pop_No_Kick
07-07-2005, 11:51 AM
Willbird

.020 crimp is a roll crimp, not a crimp with a taper die. By the way a crimp is applied to the cartridge case mouth, not the bullet. I assume you used bullet in a termnology that describes the whole works. How did you come up with a taper crimp rolls crimps?

Joe
Right, Roll Crimp the Casing mouth, not the bullet.
I did some practice crimp's. it's pretty straight forward.

This is purty much the same crimp i apply to the .357 Loads
I used a feeler gauge to measure the actual crimp.

Now I got alot of W231 Pwdr. Need to Go find some load's
for this..Also Picked up alot of Winchester Brass from the local indoor range, Storeboughts ( shot once ) ,The bbl. on the colt
is @ best fair to partly cloudy, When I was in the army. I use get lake city ammo by the can. and shoot it all in a day!
That ball ammo was never nice to my bbl. The Company armer
said that the civ. models used a diff. bbl. but they looked identical (to me) the U.S model Had the Lanyard strap
and mine also ( Did'nt say "Property of U.S. Gov't" )
My Pistol does "rattle" alot. atestament to alot of rnds thru this thing. thats normal for me because i never shot a U.S. model that was not worn-out. Any How Lets see what this
new info gonna do.!

Thanx's all of ya'll that Posted.
Chuck

Pop_No_Kick
07-07-2005, 11:57 AM
.02 is a HUGE amount of crimp with a taper crimp die, it would do terrible damage to a bullet, taper crimp dies swage the bullet smaller just from how they work, being a taper the more crimp you apply the greater the length of damaged area. Roll crimp applied to a bullet with no cannalure also causes damage but it occurs over a much shorter length.


Bill
Do ya'll STARMETAL & WILLBIRD does this crimp also apply
to a COLT .25 ACP Pocket Pistol. Old U.S Version before they Moved the operation to Spain. (this is not the collectors model)

Thanx's
Chuck.

StarMetal
07-07-2005, 12:25 PM
Yes, it's exactly the same as for a revolver round, like I said most dies have that roll crimp ledge built into them. Use to be rifle caliber dies had it too. Lee was the first, I believe, to get away from that with their famous "factory crimp" which is very good. Only thing on the 45 acp is you don't put a heavy roll crimp on it. This would apply to other automatic rounds also. Now...don't do this with jacketed bullets in automatic rounds for pistols, just enough to turn the flare in if you flare the mouths any for jacketed bullet. The friction fit of the jacketed bullet is more then lead so a crimp shouldn't be necessary. I believe most jacketed bullets for auto rounds don't have a cannelure.

Joe

BlueMoon
07-07-2005, 12:34 PM
Just a follow up on my other post. My 45acp Midway gauge wants a taper crimp of .471" to let the loaded round bottom out and my series 80 Colt's barrel let a loaded round bottom out with a tiny push (a lot less than the recoil spring would give) at .474+".

In Layne Simpson's book " The Custom Government Model Pistol", He uses a taper crimp of .470" diameter with RP brass.

I have good accuracy out of my pistol now and don't plan on trying a roll crimp with it.

Bill

Willbird
07-07-2005, 12:49 PM
Star, the article says the same amount of taper crimp was applied, IE .02" dia.

"The taper crimp reduces the case mouth to the same dia but has a swaging effect on the bullet for a much greater distance" Now that followed the statement that he used .02" roll crimp reducing the case dia to .460 at the mouth.

and I try not to use BULLET to describe a ctg. I should have said "A roll crimp applied to a cartridge containing a bullet that does not have a crimp groove."

when the ctg. case is swaged inward the bullet must move in response, jacketed bullets the jacket has some spring, in comparison a lead alloy bullet is quite "dead" and thus if you applied .o2" of taper or roll crimp, and pulled the bullet from the ctg. you would see a groove pressed in the bullet from the crimp.

Also Col. harris states that the taper crimp requires another die and another operation on most loading tools, this would lead me to belive he was seating and crimping in the same shot, which most folks do seperately in these modern times :-)

Bill

StarMetal
07-07-2005, 01:39 PM
I don't crimp in a separate operation, depending on the bullet crimp groove design. For examp RCBS revolver bullets have, in my opinion, a very nice crimp groove. From the base of the bullet the crimp groove starts with a taper, then finished with a deep crimp groove with a square face on the nose end of the bullet. Okay, you're not talking about alot of forward movement of the whole cartridge when the crimp ledge starts to engage the mouth of the case. With the RCBS type of crimp groove you can very easily seat and crimp in one operation. When the crimp begins, it's right at the beginning of the taper. As the crimp progresses, so does the taper on the crimp groove. Very nice setup and process. If you use bullets that have this type of crimp groove and you're crimping in a separate operation, you're wasting your time. Might make your head feel better, but it's not really improving the ammo. Now, there are bullet with different style of crimp grooves that do require a separate crimp operation or you will shave the bullet if you try it in one operation.

Again, on your mention of a taper crimp. You mentioned how jacketed bullets have spring back. Well what the heck are you doing taper crimping jacketed bullets? You don't need too unless maybe your brass is very thin mouthed and not gettting a good friction fit on the bullet. To even mention this of jacketed bullets here will only confuse the newbees. We're dealing with cast bullets here in this particular part of 45acp headspacing.

Now, you said this about the .020 roll crimp, except about a taper crimp: .02 is a HUGE amount of crimp with a taper crimp die, it would do terrible damage to a bullet, taper crimp dies swage the bullet smaller just from how they work, being a taper the more crimp you apply the greater the length of damaged area. Roll crimp applied to a bullet with no cannalure also causes damage but it occurs over a much shorter length.

Mr Harris said that is how much of a roll crimp that is applied to case mouth with a roll crimp die, which is standard in most dies. It just happens that this leaves the case measure at .460. Then he said to taper crimp, if you use such a die, to achieve the same .460 measurement. No where does .020 figure in with a taper crimp. If you look very carefully at the picture of the 45acp round for roll crimping specs you see that the .020 is a measurement that is taken from the face of the case mouth and going back towards the head of the case, not a diameter measurement.

I know my 45acp both guns and ammo, you're not going to win on this Willbird so give it up.

Joe

Willbird
07-07-2005, 06:38 PM
Sorry I will not just give up and bow down to your clearly superior knowledge, if you make a point that is correct I will concur, and may add details from my own experience that lead me to feel you are correct in your theory of why X+y=z. I do know my 1911 pistol and the 45 acp ctg. well enough to produce sub 1.5" groups at 50 yards from a machine rest with cast bullets.

....and yes when I have used a jacketed 45 acp bullet once in a blue moon I do leave the taper crimp die set exactly the same. (by my measurments .470 taper crimp DIA. equates to only .00125" per side, which nicely irons out any mouth bell) As to wasting time crimping seperately, I very rarely make pistol ctg. in a single stage press anymore, I have not ever tested 45 acp for accuracy with jacketed bullets, I have no desire to shoot them in the gun other than factory loaded self defense ammo.

the article says

"Roll crimp as used here means that about .02" of the case mouth is rolled over and forced into the bullet, Mouth dia is reduced to .460 see Fig 4.
"The taper crimp reduces the case mouth to the same dia but has a swaging effect on the bullet for a much greater distance" (you were correct that the .02" for a roll crimp is a length measurment not dia or radius)

They are two short paragraphs.....and I suppose one may have nothing to do with the other but the flow of the article leads me to belive that all the short paragraphs under each subject heading are interrelated.

at any rate, each man may crimp as he sees fit, and the article is quite dated, and the data could support claims for the accuracy of either roll, taper, or no crimp. I am quite sure however that a man could get by loading 45 acp for a lifetime with nothing but a normal seater die with roll crimp, but if a seperate die is required or desired for a progressive press I would buy a taper crimp die.


And Starmetal, I am also QUITE sure either of us could be assigned the job of arguing the OTHER side of this debate and do quite well with it, it is all in fun I sure hope :-)


Bill

StarMetal
07-07-2005, 06:54 PM
Bill

When you and I get deep into this stuff, such as we have, the followers of the post, who maybe be as advance, stand alot to learn.

I build my own 1911's and I know how much it costs to do so. I have to laugh at all the big name builders at what they charge. I get an even bigger laugh when some gun rag tests them out and see how they really shoot....for the giant price tag that came with them. Simply put I'll put my 1911's up against anyone's in a Ransom Rest test.

As far as crimping in a separate die, Mr Harris has an article in the same NRA book after the 45 acp one on 38 target loads. He wrote a paragraph about two, three, and four die sets and stated that there was no reason a man with a two die couldn't load as accurate ammo as the three or four die set man. In fact he stated that the most accurate ammo loaded for his test was indeed loaded with a two die set.

The 1911 is one of my favorite auto pistols and I've been shooting them, loading for them, and building them for many years. I'm on a currect project to made a 30 Luger upper for one.

Joe

Willbird
07-07-2005, 07:11 PM
I did pay quite a bit to have my 1911 built up, I however did get fancy stuff like metal checkering on front strap and mainspring housing, I would guess from a bare frame up I would have 600.00(for must haves for accuracy and longevity) in it including all the parts, GI hard slide, Clark full ramp reverse twist bbl (that was all the rage when I had it built) Lo Bomars, it had a 4lb trigger, now I had it re-done to 2.5lb with a carbon trigger.

I had the firing pin centered and re-done to 38 super size, makes pretty fired cases that way. It is practically as accurate as my model 41 pistol tho...bigger bullet makes up for the slightly larger group size hehe.

going back and forth from a bomar rib to the low bomars cost me some extra bucks along the way.............but the only thing I "needed" money for then was beer, dope, and DUI tickets....and now I live cleaner and smarter, and have less spending money, and I am glad I have that 1911.....I just wish I had the cash to do a 9x21 that would shoot as good or better.

My dad told me as a little shaver that we seat and crimp seperate...and prefferred to not crimp at all (brass lasts longer)...wadcutters in the star press were setup tho to seat and lightly crimp in one pass...I have no doubt that it can be done with some types of bullet and a bit of fiddling.BUT and a big but, I would start the little shavers off seating and crimping seperately......they need practice moving the press handle up and down anyway hehe :-)


Bill

StarMetal
07-07-2005, 07:31 PM
When you set up a match barrel you set it up so the locking lugs on the barrel fully engage the recesses on the slide. If you do this you'll find that your firing pin hole becomes off center, in some cases, waaaay off center. So you have to center it. I've done this quite a few times. Very simple and doesn't take very long to do it.

As for the 38 firing pin....I mentioned I built a 38/45. Well if you get into hot loads for it, and those were never the intention for the development of the round, you'll find that the high pressure will cut little metal donuts from the primer cup. That's where the primer cup flows back into the firing pin hole from pressure and at the same time the slide is unlocking, so it cuts that little bit of metal off. Cure? 38 super/9mm firing pin.

I don't care much for the Bomar ribs. Too much mass atop the slide for my taste. I like the raised rib such as on the Gold Cups or even a milled flat. The fancy triggers (carbon, aluminum,etc.) are just whiz bangs that really don't have anything to do with lock time or accuracy. Personally I think the titanium firing pins are a waste of money.

I build my guns for the costs of parts. Sure came in handy knowing how to put them all together and tune them.

Joe

Willbird
07-07-2005, 08:26 PM
My smith actually sinks the bbl a bit higher up into the slide.

the carbon trigger I got cause it looked cool.


I fit and chamber rifle bbls myself and I agree it is nice to do it WHEN you want, HOW you want, and for less money. and later on when you wear out the bbl the new bbl will fit all your old brass because it was cut with the same reamer.


Bill

StarMetal
07-07-2005, 08:38 PM
The only way you're going to seat a barrel deeper then mine is to either mill the slide or the barrel and I don't recommend either. I know how far off my firing pin was from center when seating my barrels fully and would be shocked thinking of the angle on the firing pin ange on your pistol if he seated higher.

Now that I think about it, that makes for alot of other problematic adjustments. One is the barrel is going to be at a greater angle to the barrel bushing.

Joe

Willbird
07-07-2005, 09:11 PM
He has a boring bar he made to re-cut the lugs in the slide, he has been at this awile and I trust him to know his way around it, It is not much, maybe .01-.02 as I recall, it ends up a decent percentage more engagement tho, and once again as I recall the GI hard slides the lug spacing needs slight adjustmant to bear on all the lugs.

the small firing pin was for 45 super, way back then you needed, full ramp bbl, and small firing pin, plus a heavy spring, all you need now is the heavy spring with the new tougher brass.

Bill

P.S. and I didnt like the bomar full rib either, sounded neat, looked neat, but limited what the gun could do too much.

StarMetal
07-07-2005, 09:24 PM
If the match barrel is fully seated there's no need for further lug engagement. Must have been his own personal quirk. None of the other big boys do it, unless requested, which then they'll do anything. With newer slides and match barrels the lugs match up pretty decent. On my set ups the barrels hit the top of the slide, there's no going any deeper.

Joe

243winxb
08-01-2005, 10:35 AM
If the end play is taken out of the round when in the chamber, accuracy will be improved (accurate target gun). With a cast swc bullet this means the lip of the bullet(the lead just above the brass) should just slightly engage the rifling. A problem occures if the over all length gets to long, the action will not close correctly. On cast bullets, because of different mixes of alloy, the OAL is not a good measurement to go by. The measurement you need to stay constant(the same) is the distance between the head of the brass and the lip of the bullet (the part of the bullet that takes the rifling.), Taper crimp works best with mixed brass, brass of the same lot and maker is more accurate in a target gun. Not all 45acp autos will let you seat the bullet this way. Best cast bullet i have found is the Lyman 200gr, bevel base. Tho a pain to lube with the bevel base.

Char-Gar
08-01-2005, 05:24 PM
Ya just gotta love this board! You guys can take something so simple as loading a 45 ACP round and turn it into rocket science.

1. Seat the bullets until the base of the loaded round is dead even with the rear of the barrel hood. Matters not where the case mouth lands! You now have case head properly held against the breech face of the slide.

2. Use either a taper or roll crimp to reduce the diamter of the case mouth to .470 (plus or minus a thou or two). Matters not which kind of crimp is used. If you don't use some method to turn the case mouth back into/toward the bullet you will get some jams.

3. Shoot the darn thing!

Hard to believe it is that simple..but it is!!

NVcurmudgeon
08-01-2005, 07:05 PM
Chargar, The first cartridge I ever loaded was .45 ACP, about 1959. I stumbled onto the barrel hood as OAL gauge method early on and never looked back. Another advocate of the simple life.

Char-Gar
08-01-2005, 10:01 PM
NVCurmudgeon..I thought every used the barrel hood as an OAL gage! If you start measuring 45 ACP cases you will find a huge difference in length. To much difference to make headspacing on the case mouth a way to acheive good accuacy. To my way of thinking..that shelf in the chamber is there to prevent EXCESS headspace and not to maintain proper headspace. It is just a safety feature.

I started loading the 45 ACP round in the autopistol in 1961, so you have a couple of years on me. I did allot of Bullseye shooting in those days. Even today, the 45 ACP and 38 Special rounds are on the top of my list of hangun rounds worth their salt.

NVcurmudgeon
08-02-2005, 01:19 AM
Chargar, I've measured a jillion .45ACP cases and found none that were long enough to be "overlength." I once had a composite .45 with GI frame and Commander slide, the first all-steel Commander I ever saw, back about 1966. It would not function with factory ammo, but was OK if the cases did not exceed .880." I've often wondered what the lowlife who stole it did after he ran through the 14 rounds he got with it!

swheeler
08-02-2005, 01:27 PM
NVC: hopefully he accidentally shot himself with it!!!!
Scooter

Char-Gar
08-02-2005, 04:11 PM
NVCurmudgeon...Like you, I have never found any "too long"..I have found allot that were just right and and several varieties of too short. None that could not be compensated for by proper bullet seating.