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1/22/2020 12:12:56 PM
Posted: 11/17/2012 10:47:52 PM EST
[Last Edit: 11/17/2012 10:49:24 PM EST by 1911smith]
Normally, I won't bother with gun rags unless I've heard there's an article of interest. I bought the second this year, Guns & Ammo December, 2012. Before it my last was American Handgunner issue with Taffin's review on my friends work, Jason Perkins and a color case hardened pistol. Still haven't read that one cover to cover yet. Patrick Sweeney wrote an article on crimping pistol cartridges. I know of Patrick, his writing, competitive shooting and the fact he's an extremely talented pistolsmith and member of American Pistolsmiths Guild which ain't no easy task. To be admitted ones work is judged by their piers. Think big name, world class smiths judging quality of your work. Patrick has passed the scrutiny of many and in no way would I suggest to be his equal or possessing more firearm knowledge but crimping 0.004 to the negative ?


Magazine is on magazine racks now, anyone read the article yet ? If so what's your thoughts ?
Link Posted: 11/18/2012 5:09:11 AM EST
Didn't read it. What is he crimping -.004? Taper crimp pistol or roll crimp revolver? If it's taper -.004 is way to much as far as I'm concerned.
Link Posted: 11/18/2012 5:42:08 AM EST
[Last Edit: 11/18/2012 5:42:17 AM EST by xtreme762]
The article is in Guns & Ammo, correct? Sounds real interesting.
Link Posted: 11/18/2012 5:48:47 AM EST
Link Posted: 11/18/2012 8:06:19 AM EST
[Last Edit: 11/18/2012 8:07:17 AM EST by SteelonSteel]
I'm always told by an older reloading friend to have an open and inquisitive mind. He also says the only way to know if it works is to try it. So maybe an experiment would be in order to decide if it works for you and your gun. Would really need a ransom rest to do it properly.

On initial thought as a cast boolit shooter I'm not warm to the idea of over crimping my bullet and effectivley sizing it even smaller than what the barrel wants.
Link Posted: 11/18/2012 11:00:12 AM EST
Originally Posted By SteelonSteel:
I'm always told by an older reloading friend to have an open and inquisitive mind.

On initial thought as a cast boolit shooter I'm not warm to the idea of over crimping my bullet and effectivley sizing it even smaller than what the barrel wants.



Patrick backtracks a few paragraphs into his article and says. " Now, not all bullets, nor all cartridges, are happy with this measurement method. If you find accuracy goes all to hell with the calculated crimp, you will have to experiment."


I forget. Who said Patrick Sweeney advocated negative 0.004 crimp on all reloaded cartridges, or something to that affect ? My point ? Crimping whether it be a zero sum or heavy crimp are not evil. Although negative -.004 is a bit excessive.

Link Posted: 11/18/2012 3:29:53 PM EST
I am not even sure what a negative -.004 crimp means or how Sweeney makes the measurement. But, I like a heavy roll crimp on my 44 mags to 1. prevent bullet creep in revolvers and 2. to assure good feed in my '92 Puma lever gun. I have seen photos of Dryflash3's large cal. pistol roll crimps. I dare say they are more than negative .004.

PS: I think Sweeney has or had an account on ArfCom.
Link Posted: 11/18/2012 3:38:29 PM EST
[Last Edit: 11/18/2012 3:41:10 PM EST by SteelonSteel]
Originally Posted By CCW:
I am not even sure what a negative -.004 crimp means or how Sweeney makes the measurement. But, I like a heavy roll crimp on my 44 mags to 1. prevent bullet creep in revolvers and 2. to assure good feed in my '92 Puma lever gun. I have seen photos of Dryflash3's large cal. pistol roll crimps. I dare say they are more than negative .004.

PS: I think Sweeney has or had an account on ArfCom.


I can only assume it's tighter by 0.004 than straight parallel walls but for good communication I'd like to be certain it's 0.004 total and not 0.004 per side.

Link Posted: 11/18/2012 4:11:26 PM EST
I posted this in another thread.

Adjectives are very poor substitutes for numbers. This has become my pet pieve, why ? Because this creates unnecessary confusion and endless posts that start with.

"Is this enough crimp." Ending with. "My cartridges won't feed."

Then the poor fucker winds up in some 1911 forum somewhere being told he needs everything from new recoil springs to send it off to a competent smith. In between these suggestions are new magazines, extractors and shooting lessons.


It's simple math but what do we tell folks ? Set the die to where it just removes the flare. Last time I checked no one makes a "remove the flare die." Not Dillon, Redding, RCBS, Lee, Hornady, NOBODY.

EVERYONE mentioned makes a crimp die and setting a crimp die is done like everything else reloading, by computing simple elementary grade math. Looks something like this. ( bullet diameter + brass casewall thickness x 2 = maximum setting for crimp die. So if we have a .355 bullet using Winchester brass and we want TO SET THE CRIMP DIE, elementary level math looks like this.

(.355 + .010 x 2 = .375) So with these numbers I take a belled or "flared" piece of brass, place in shell holder, extend ram and run my CRIMP die down tight on belled case that I belled .004 over sized case mouth. Then crank my CRIMP DIE down anywhere from a half to three quarters a turn further and lock.

No crimp at all, still requires the use of a crimp die, meaning a CRIMP has been applied.

Now, take the same numbers from above. (.355 + .010 x 2 = .375) Although we, with experience know what removing the flare is. What we take for granted is how this is perceived. Think back when all this was new and your overwhelmed. Someone, somewhere taught you the math for a ZERO SUM CRIMP. If not, then maybe you were touched and figured it all out because, well, your smart. Whatever..... Most folks need voltage before the light comes on.

Ok, let's look at zero sum crimp, light crimp, medium crimp and heavy crimp. You won't find this written down anywhere folks. This is what teaching others has netted.

Bullet diameter + case wall x 2 = zero sum crimp. This is, 0.000 (zero). Light crimp is - 0.001 (negative one thousanths). Medium crimp is -0.002 (negative two thousanths). Heavy crimp is -0.003 (negative 3 thousanths).

Someone said Patrick Sweeney had a book out on reloading. In his book he suggested 0.004 crimp ? I'll have to get that book, but that's excessive. Some history on Patrick takes him back in time before IPSC, through IPSC and into USPSA. Knowing his history I have no problem believing this because these sports reward speed far more than accuracy. Modern ammunition manufacturing crimps to negative three thousanths, heavy crimp. So Patrick's a bit off the chart. Said this just because I knew it would come up again. Didn't respond when posted but it can't be let go without discussion. Patrick has been around long enough to know negative four thousanths would not win him a bullseye match. For most of the new guys, just finding something that works is challenge enough and we've all been there.

Someone, one time made the mistake of saying. " Well that's all good and fine but some of us are math impaired ! " Ok, I said. If you think about it we measure oal with a caliper, powder by grain on a scale that measures by grain, we use dial gages to measure things like primer depth and cartridge neck runout. What you're really saying is you're "reloading impaired.".


Link Posted: 11/18/2012 4:54:00 PM EST
So it is .004 on the dia, .002 on the radius. I doubt one could even see .002 on the radius. Not much of a crimp, IMO. I like to tuck down the end of the case into the space between driving bands, or the cannelure space, until you can hardly feel the edge of the case when you draw your finger over the joint.
Link Posted: 11/18/2012 5:05:42 PM EST
Originally Posted By dryflash3:
I read it. I'm not changing what I do.


I read also and I ain't changing my ways either. He may be a top line gunsmith, but that doesn't make him am expert on reloading by any stretch.
Link Posted: 11/18/2012 5:09:16 PM EST
Originally Posted By 1911smith:
I posted this in another thread.

Adjectives are very poor substitutes for numbers. This has become my pet pieve, why ? Because this creates unnecessary confusion and endless posts that start with.

"Is this enough crimp." Ending with. "My cartridges won't feed."

Then the poor fucker winds up in some 1911 forum somewhere being told he needs everything from new recoil springs to send it off to a competent smith. In between these suggestions are new magazines, extractors and shooting lessons.


It's simple math but what do we tell folks ? Set the die to where it just removes the flare. Last time I checked no one makes a "remove the flare die." Not Dillon, Redding, RCBS, Lee, Hornady, NOBODY.

EVERYONE mentioned makes a crimp die and setting a crimp die is done like everything else reloading, by computing simple elementary grade math. Looks something like this. ( bullet diameter + brass casewall thickness x 2 = maximum setting for crimp die. So if we have a .355 bullet using Winchester brass and we want TO SET THE CRIMP DIE, elementary level math looks like this.

(.355 + .010 x 2 = .375) So with these numbers I take a belled or "flared" piece of brass, place in shell holder, extend ram and run my CRIMP die down tight on belled case that I belled .004 over sized case mouth. Then crank my CRIMP DIE down anywhere from a half to three quarters a turn further and lock.

No crimp at all, still requires the use of a crimp die, meaning a CRIMP has been applied.

Now, take the same numbers from above. (.355 + .010 x 2 = .375) Although we, with experience know what removing the flare is. What we take for granted is how this is perceived. Think back when all this was new and your overwhelmed. Someone, somewhere taught you the math for a ZERO SUM CRIMP. If not, then maybe you were touched and figured it all out because, well, your smart. Whatever..... Most folks need voltage before the light comes on.

Ok, let's look at zero sum crimp, light crimp, medium crimp and heavy crimp. You won't find this written down anywhere folks. This is what teaching others has netted.

Bullet diameter + case wall x 2 = zero sum crimp. This is, 0.000 (zero). Light crimp is - 0.001 (negative one thousanths). Medium crimp is -0.002 (negative two thousanths). Heavy crimp is -0.003 (negative 3 thousanths).

Someone said Patrick Sweeney had a book out on reloading. In his book he suggested 0.004 crimp ? I'll have to get that book, but that's excessive. Some history on Patrick takes him back in time before IPSC, through IPSC and into USPSA. Knowing his history I have no problem believing this because these sports reward speed far more than accuracy. Modern ammunition manufacturing crimps to negative three thousanths, heavy crimp. So Patrick's a bit off the chart. Said this just because I knew it would come up again. Didn't respond when posted but it can't be let go without discussion. Patrick has been around long enough to know negative four thousanths would not win him a bullseye match. For most of the new guys, just finding something that works is challenge enough and we've all been there.

Someone, one time made the mistake of saying. " Well that's all good and fine but some of us are math impaired ! " Ok, I said. If you think about it we measure oal with a caliper, powder by grain on a scale that measures by grain, we use dial gages to measure things like primer depth and cartridge neck runout. What you're really saying is you're "reloading impaired.".




Good explanation and what I presumed as it's the logical way to measure with our tools, total diameter. Only a technical artist drawing a cartridge drawing would display at 0.002 a side because they're drawing it not handling a measuring tool.
Link Posted: 11/18/2012 5:15:42 PM EST
I have for several years now used Patrick's info on crimp measurement. In a article he wrote(can't locate), the 9mm was at .372 for jacketed and .376 for lead. I read this and began measuring current factory FMJ and some of my on hand lead loads. I found that he was pretty much on with these numbers. ALL of the factory ammo measured at the .372 area and my years of lead competition loads were right at the .376. It would seem that there is some clarification needed, perhaps someone should email him for a quick check. I used to know his handle and where he could be reached, but do not have it handy.
Link Posted: 11/18/2012 5:35:08 PM EST
he hangs out on T. O. F. and uses his name for his handle

Link Posted: 11/18/2012 5:52:14 PM EST
Patrick says everything that needs to be said in his article. The problem is he leaves an impression that a negative .004 crimp is the rule and not the exception. His advice is great for those with feed issues or want feed assurance. If your thing is gettin a lot of rounds out of the barrel real fast and your idea of accuracy is the A zone on a USPSA target his advice is good. Another thing, measuring crimp diameter on factory ammunition is an eye opener. I wish everyone would make a trip to where ever factory ammunition is sold with caliper in hand.

What Patrick doesn't do is expand crimp adjustment methods for improved accuracy. I'm kind of the FCD advocate when folks get down on what they may or may not understand.

Here's the next post I made in thread from previously quoted post.

Beings you're new to this and these cartridges are new for your gun and don't have a firm grasp on tailor making cartridges to a specific feed channel. Yes, I'd recommend a medium crimp.

Now someone's gonna come along and say BS and my unsaid reaction will be, .

Take your caliper with you sometime to a gun shop. Tell them what your doing and you'd like to see every make and type of cartridge they sell. Mine said sure and starting hauling boxes from behind the counter. Bass Pro didn't give me a second look. Measure loaded case mouths on pistol cartridges. Lee didn't name their factory crimp die what they did for nothing. Almost all ammunition makers crimp by at least .001. Hornady has been the one exception and guess what ? Hornady now crimps their Critical Defense ammunition. The reason most use for not crimping is because straight wall pistol head spaces off the case mouth. While true, your weapons feed channel depends on bullet ogive to navigate its way to chamber. Setback can really screw with feed geometry. At a minimum use a light crimp until you get to know the craft a little better.

By the way. I can't hand groups of heavy, medium, light or zero sum crimped cartridges to a novice shooter a discern a difference in crimp by their groupings. People go overboard to make this an issue when it's not.



Here's the thread in context. Question on working up a load.

My load pistol load work ups include adjustments in crimp and oal. When doing load work on range feedback is instant. So, hell yes. If someone could get Patrick to weigh in that would be great.
Link Posted: 11/20/2012 10:30:15 AM EST
Patrick says everything that needs to be said in his article.


DC,
I have looked at Dec. 2012 and Nov.2012 issues of G&A. I cannot find the article you refer to.
Please check the date again.
Link Posted: 11/20/2012 11:01:14 AM EST
[Last Edit: 11/20/2012 11:02:42 AM EST by 1911smith]
Guns & Ammo/Handguns, December 2012/January 2013. Cover reads, Pony Power, Colt's Mustang .380 auto gets a great makeover.. Pictured is a Mustang Pocketlite chambered in an almost useless .380 acp caliber. Visions of a self engineered 9mm conversion dance through my mind but haven't started contemplating if possible yet.
Under the Colt in yellow letters, cover reads BULLET CRIMP, solve reloading's toughest riddle. Sounds great the riddles finally been solved on page 14, but flip to page 16 and you find there are multiple underlying riddles that no one answer will solve. But, the overall article is very well done and informative. The problem for me at least is the impression left on some new reloaders who commented in this forum Patrick Sweeney advocated a negative .004 crimp on all loads and much to my surprise no one said a word. In days gone by the mere mention of a crimp in this forum has started some very lively discussion. Throw in an fcd and we had an all out bar brawl. Which is exactly what a poster by the handle of David Clark has started in the reloading forum of 1911 forum.com by mention of article and introduction of elementary level math prior to reading article. (Pretty laid back bar brawl.) Several have commented that anything more than the mention of " just remove the flare" over complicates a simple issue. That is a good forum though, bunch of crusty old fuckers, but at least I'm the kid over there instead of the same old, tired fucker over here.

Patrick's article is with one exception, spot on.


dc.
Link Posted: 11/20/2012 11:06:42 AM EST
Originally Posted By dryflash3:
I read it. I'm not changing what I do.


Are his methods significantly different or similar to your processes? How so?
Link Posted: 11/20/2012 11:14:53 AM EST
Patrick Sweeney has probably loaded and shot more than most of us will, and when he bothers to write something, I'll listen to it. Doesn't mean I won't disagree, but it's at least worth trying out.

I was happy enough riding in the "remove the bell" camp until I did some Ransom testing of a gun I'd built for a friend, a Master-level USPSA shooter who has at least 15 years and 300,000 rounds on me.

I was shooting my 124gr 9mm reloads and getting a fist sized group at 25 yards. His loads were shooting into a half dollar-sized hole. They were crimped far more than I would have ever considered, almost looking like a roll crimp. He was using the same bullets I was and a similar load (3.8 gr of Titegroup).

When I spoke to him about it, he told me he always heavily crimped his 9mm ammo. I tightened my crimp die down and sure enough, that helped out the accuracy of my loads. The upshot is that experimentation is critical if you want to achieve the best accuracy for any given caliber.

Link Posted: 11/20/2012 11:15:55 AM EST
dc,
thanks. I was looking at G&A not G&A / Handguns.
Link Posted: 11/20/2012 12:08:50 PM EST
[Last Edit: 11/20/2012 12:09:30 PM EST by kingston_fisher]
Originally Posted By 1911smith:
I posted this in another thread.

Adjectives are very poor substitutes for numbers. SNIP



Thanks for posting that. That is probably the best non visual description of the crimping process I've encountered.
Link Posted: 11/20/2012 3:01:53 PM EST
Will do you one better.

This is how I flare or bell straight wall pistol brass that's been sized. I set expander to bell 0.004 over sized case mouth. Then index brass directly to crimp die without seating a bullet. I then run crimp die all the way down on flared case mouth, remove case and turn die 3/4 turn. This usually gives me a light crimp of negative 0.001.

Afterwards flare case again, set seating die to desired seating height, then index to crimp die for crimp and dial die to desired crimp. Then lock ring down with crimped cartridge inside die so die doesn't turn quite as easily.
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