Lee Factory Crimp/Cast Bullet Modification

[flat top]

I know what you mean!.............Ok, we will put an end to this until you try out that crimp, but, be forewarned...when you go to the range, and folks start honoring and praising you for your ballistic prowess....just remember..."its the crimp"! Let us know the results!!!! We will now return to our normal programming.

 

[Skip Sackett]

ft, they have been doing that for MANY, MANY years already!

 

[flat top]

Oh, I dont doubt that at all!!!

 

[flat top]

Well, I had a little time to do some research on Lee Crimp Dies, and found out some very interesting information from "users" of the dies, and from some independent tests that had been conducted. First off, I can not find anyone who will refute the "fact" that this type of crimp, when used properly (heavy/firm crimp) results in better accuracy/velocity uniformity/standard of deviation, etc, statistics. This has been my personal experience, and the experience of folks that I know who swear by this type of crimp. In every case, there has been an improvement. Also, folks that have had problems with bullet jump in heavy revolver loads have also solved that problem with this type of crimp. In both rifle and handgun cartridges, there has also been a drastic improvement in the concentricity (runout) of loaded rounds, which of course will aid in accuracy. The tests that were done show that the Lee Crimp far exceeds any other type of crimp in pull factor and compression yield tests, by a wide margin............I have never been a big fan of Lee products, but, using this type of crimp that the Lee Crimp Die applies for many years , I think that this is Lee Precisions greatest contribution to the reloading hobby. As discussed in this thread, there may be some issues with some Lee Factory Crimp Dies, but, with those issues resolved the crimp itself and the performance gained by using it is well worth the effort to make the modifications if your die requires that.

 

[Gun 4 Fun]

I have been doing a little reading on some other forums since this thread started, to see what others might be saying about this type of crimp. I see there are others who seem to agree with FT on this subject, and quite adamantly by some. I need to do some further reading on it, but it seems interesting.

 

[Skip Sackett]

The point is if they already have a Lee seating die, they have no need to buy another to have it modified.

I'll tell you what FT. I'll help you with this when the time comes.

Get some equipment together, make some loads with and without this world famous crimp, go to the range, make a video on a digital camera and post it with your chronograph results.

If you need a camera, I'll send one as long as you promise to send it back when finished. I'll even upload it to the web for you!

As soon as I/we get out of this snow I have a trip to the range all set up. But if you want to beat me to the draw, let me know where to send the camera.

You will have to go to a range to use it though!

p.s. If you want to use my chronograph let me know that in your pm too!

 

[Scrapper]

Well, I had a little time to do some research on Lee Crimp Dies, and found out some very interesting information from "users" of the dies, and from some independent tests that had been conducted. First off, I can not find anyone who will refute the "fact" that this type of crimp, when used properly (heavy/firm crimp) results in better accuracy/velocity uniformity/standard of deviation, etc, statistics. This has been my personal experience, and the experience of folks that I know who swear by this type of crimp. In every case, there has been an improvement. Also, folks that have had problems with bullet jump in heavy revolver loads have also solved that problem with this type of crimp. In both rifle and handgun cartridges, there has also been a drastic improvement in the concentricity (runout) of loaded rounds, which of course will aid in accuracy. The tests that were done show that the Lee Crimp far exceeds any other type of crimp in pull factor and compression yield tests, by a wide margin............I have never been a big fan of Lee products, but, using this type of crimp that the Lee Crimp Die applies for many years , I think that this is Lee Precisions greatest contribution to the reloading hobby. As discussed in this thread, there may be some issues with some Lee Factory Crimp Dies, but, with those issues resolved the crimp itself and the performance gained by using it is well worth the effort to make the modifications if your die requires that.

Hey FT, I agree with you on this "Whole Heartedly" after learning these things working beside my Dad in the mid 70's. We would go shooting every weekend, if we weren't hunting, and test our hand-loads of 30-06, 30-30, and 38 special(some others). We proved to ourselves that how the bullet was inserted was very important to accuracy especially when compressing powder. A nice firm uniform crimp made these loads scary accurate. After we test patterned and sighted in we used to shoot bouncing rolling targets (made of 18" Dia. round 3/4" thick wood blanks) freehand. Practicing this made us very good at running shots. We bagged many deer with running shots. Anyways I like this thread a-lot, it's a very productive one.

Have a Great Day Folks

 

[RCleveland44]

I'm not sure what Lee calls it, but their crimp is distinctly different from either the standard roll or taper crimp of the RCBS type dies; regardless of whether the sizing ring (actually I didn't realize there was one, is this a new feature?). Because the crimp applies pressure from the sides of the neck rather than by pushing in from the top, I've found them especially useful when reloading very thin brass that may tend to buckle under normal crimping pressure like the 38 and 44-40's.

 

[Scrapper]

The Factory Style crimp has been around a very long time. It just seems as though they didn't make any of these dies available to the general public until recently.

 

[flat top]

Back in the day (I love that term...kind of adds a nostalgic flavor), all we as reloaders had was the roll crimp. With heavy cast bullets, and max loads it was all we could do to keep bullets from jumping the crimp. To solve that problem (which many reloaders still do to this day), we would drastically undersize our expanders and apply such a firm roll crimp that the case was near collapse!!! This solved the jump issue, but, didnt do much for runout....we had "power", but accuracy was marginal. Then came the Lee Die and it was a whole new ballgame! As time went on, the bullets got heavier, and because of that, longer. Now, with these big heavy bullets sitting very near the end of the chamber in revolvers, the jump issue becomes more critical, and the Lee Die more important to those that shoot these heavy for caliber bullets, or like RCleveland44 stated, cases with thin walls. Nothing matters when you use the Lee Crimp method, and as far as I am concerned it is perfect for any application. To clarify the modification (again!!!!): This modification was used on the "Lee Carbide Factory Crimp Die". There is a carbide insert in the bottom of the die, that sizes the loaded case during the crimping process. This is most helpful when you are reloading semi auto pistol ammo, and adds to reliability. Where the sizing is not necessary (most revolvers), and where over bore size cast bullets are used, the carbide sizer (an insert in the bottom of the die) will size down the case and the bullet. My .432 bullets are now "undersized" for my bore requirements, and accuracy suffers because of that. To eliminate that issue, I opened up the carbide insert to allow the oversized bullet and the case to pass freely through the carbide insert and not affect the size of the bullet..............By the way, in doing my research, I found one fella that cut the bottom of the die off just above the carbide insert. I dont know if that is wise or not because the cartridge still needs to be reasonably centered for the crimping process, but, it would be an alternative to my method if somebody would care to try it.

Scrapper; We used to blow up ballons for the same purpose, and on a windy day with snow on the ground, it was really a hoot to test our shooting skills....much fun!!!!


SC; I never said that anybody had to buy anything....If they have a Lee die that can apply the same crimp thats good...if they have a Lee Carbide die, I offered up a solution to a possible problem..........I dont have to "prove" this to anybody...this whole issue of the proper (heavy) crimp has been proven long ago by many shooters. I was skeptical at first, just as you are, but I tried it (open mind)...it worked....and I have been using it ever since. Try it if you want...dont try it....It makes no matter to me! By the way, some helpful hints if you do try it. You "may" have to polish the crimping collet/seat on your die. It has been noted that "some" Lee crimp dies have machine marks that cause the crimping collet to stick a bit. Also, if for some reason your accuracy does not improve, next time you crimp, crimp the case, then lower it a bit, turn it 180 degrees and crimp it again. "Some" Lee dies have been found to be a bit out of tolerance, but this will solve that issue. Knowing how to use the die, or correct or "fudge" a bit may be helpful with "some" Lee crimp dies.

 

[sunday bill]

I have never had issues w/ magnum rounds fitting in any revolver. I find the LFCD counter productive to accuracy w/ lead bullets. One could certainly go the route as FT did, but a properly sized case & a good roll crimp have sufficed for my revolver rounds for years. Same for pistols, a good taper crimp is all that is needed. I think Lee came up w// this little gimick to acount for poor tolerances of their sizing dies. AS always, JMO.

JMO2

My experience was with Schofield brass.

 

[flat top]

Bill; What kind (brand) of Schofield do you shoot?

 

[Bearcat74]

I tried my new 310WFNGC .430" bullets through my LFCD today and they were sizing the loaded round down .002". I went out to the shop and chucked up a Tungsten/Carbide cutter in the old dremel, cranked it up to 32000 rpm and went to work. Through my saftey glasses i could see chunks flying as I was trimming the carbide ring and making it bigger. All I managed to do in 35mins is destroy the carbide cutter, it wouldn't cut butter now. The ring in the die looks good as new after some sandpaper polishing, no diameter change.

I worked with the crimp on my seating die and I have a good looking crimp from out. Do you guys have good luck using the crimp from your seating die?

 

[flat top]

Bearcat; This is the crimp that my LCFC applies to the case...this is the heavy crimp...the only crimp I use. Some on here have said that the Lee seating die "will" crimp just like this.

 

[Skip Sackett]

I worked with the crimp on my seating die and I have a good looking crimp from out. Do you guys have good luck using the crimp from your seating die?

Only for the last 20+ years or so!
Yes, the answer to your question is yes and here is what it looks like when it is installed like 99% of folks do.

Left to right: 38spl, 44Mag, 500S&W

 

[Bearcat74]

flat top, that is more crimp than I use. I tried that crimp and my gun shot better with 1/2 turn, is your crimp 1 full turn? Now my 686 with 158 XTPFP over H110, aweful until I hit the crimp you show, 1 full turn.

Smith Crazy, that is what my seater crimp looks like. There is something wrong with the cartridge on the far right, it appears to be suffering from giganticasizm. The 44 looks to be intimidated and the 38 is simply afraid. I think that they have bullet envy.


Thanks for the pictures guys.

 

[flat top]

Bearcat74; Other than the 10 grain of Unique/250 @1000 load, all I shoot are the heavyweights (300+) at near max charges. The heavy crimp that I use is a standard for the heavy loads amongst everyone that I know, but, it does not affect the accuracy of the Unique load. I use it for all my loads now and just leave the die set were it is. If you go back through this thread, I give the info on how to properly set up this heavy crimp. It is important that the crimp be confined to the width of the crimp groove on the bullet, so the crimp seats against the inside band of the crimp groove and supports the forward driving band at the top of the crimp, and sits squarely on top of the driving band at the bottom of the crimp groove. Also some Lee dies are a little bit off tolerance, and after you make your first crimp, lower the cartridge a bit, turn it 180 degrees, and crimp the cartridge again. That may help. I use the Lee Carbide Factory Crimp Die, not the Lee seating die. SC uses the Lee seating die and says (in a previous post) that it will apply the same crimp that I have shown, and, I believe he supplied photos of that. Also, if you have loads that are accurate with the crimp you normally use, and you just apply the heavy crimp that I use, there is a chance that the accuracy of that load may change, What I had said in a previous post is, that you need to set up for the heavy crimp first, and then work up your load. This heavy crimp has been proven by thousands of shooters to improve your loads....I have proven it to myself (although I was skeptical when I first tried it), and the gains by using this type of crimp far exceeded my expectations. Good Luck, and if you need help you can email me, I will be more than happy to respond.

 

[flat top]

SC; maybe 99% of the folks in your world....not mine. Hey, you said you are going to try out the heavy crimp.....well?

 

[Skip Sackett]

Have no fear,

SC; maybe 99% of the folks in your world....not mine. Hey, you said you are going to try out the heavy crimp.....well?

I am going to the range sometime this week, hopefully. I don't know if you have been getting the weather we have but, I ain't going to the range when it's still trying to put down a blanket of snow! Just getting too old for that kind of stuff anymore!

I will tell you this though, my word is good. I will run it over the chronograph just as soon as practical!

 

[Skip Sackett]

New title for this thread!

flat top, that is more crimp than I use. I tried that crimp and my gun shot better with 1/2 turn, is your crimp 1 full turn? Now my 686 with 158 XTPFP over H110, aweful until I hit the crimp you show, 1 full turn.

Smith Crazy, that is what my seater crimp looks like. There is something wrong with the cartridge on the far right, it appears to be suffering from giganticasizm. The 44 looks to be intimidated and the 38 is simply afraid. I think that they have bullet envy.


Thanks for the pictures guys.

Bear,
We can get the crimp that FT gets by burying our dies into the case and save ourselves some money, time and I'm sure frustration. I guess this thread should be titled: "Look what I could have done with a standard Lee seating/crimping die if I would have bought them instead of RCBS!"

(Just kidding)