***.40 S&W crimp question***

[rsplante]

I know, I know, this is a rifle forum. But I have a problem and this is my favorite go-to source for information about reloading, and I know that many of you have experience in both rifle and pistol reloading. For the last two or three years, I have been reloading for, and competing in F-T/R at 200, 300 and 600 yd. Today I tried my first USPSA competition. It was ugly. I kept getting a failure-to-feed problem (maybe 30% of the time.) Several people identified it as not enough crimp. I am shooting .40 S&W with plated Rainier 180 gr. bullets. My understanding was that I should only remove the bell. They say that I should barely be able to feel the rim of the case.

More data. I am shooting a Glock 35 (which is hardly a Glock anymore.) I have a gunsmith fitted BarSto barrel, a Pyramid trigger, a tungsten guide-rod, slide cut down by BarSto to accomodate a Trijicon RMR sight, and a Zevtech magwell.

Does anyone have an opinion on the wisdom/safety of possibly overcrimping a .40 S&W round? Does anyone have a good method of determining the proper crimp. One suggestion I received was to run a black magic-marker around the transition and then recrimp. They said something about having a fingernail thickness of brass showing. Did not get a good explanation, but things were pretty fast-moving for me on my first competition of this sort, combined with being discombobulated by the constant FTF problems.

 

[OF&B]

I shot for leaving the case mouth .0005 - .0015" over the diameter of the case around the bullet. It's easy to measure with a digital caliper. I ran a G22 in IDPA with a series of Storm Lake barrels. The one currently in the gun is a fitted BarSto. The fitted barrel didn't do anything for accuracy that the drop in barrels didn't. Glocks lock up completely differently than 1911s. I made SSP master with the Storm Lake set up and Berrys plated bullets.

Did you chamber check your rounds in the actual gun barrel? You might check that the barrel has a forcing cone cut in it. BarSto delivers some of them short chambered and some smiths miss it.

My experience as an IDPA novice was most of the advice given was mythology passed on by perpetually mediocre shooters.

 

[MarkCO]

First check that chamber. Remove barrel, drop a fired empty in the chamber, then a loaded round...compare. If they are equal, you are likely fine. Next makes sure your OAL is not over 1.135". If it is, especially with the plated bullets, they can hang and induce feed problems.

If those are all good, then it is probably a fit issue of the barrel. Over-crimp plated bullets and you get another set of problems.

 

[JByrd]

the way i had it explained to me was, casemouth should feel smooth when you run your finger across it.i was concerned as well b/c i got some plated bullets i run. i did a accuracy test with no crimp , what i perceived as smooth/correct and finally excessive crimp 20 rds each.

i had no issues out of any of them feed wise and i believe the accuracy was best on the propper and excessive groups.

gun was xdm 5.25

what # recoil spring are you using

do you drop your loaded rounds into your uninstalled barrel turn barrel over and make sure loaded round fall out "drop test" this may be especially important with that match barsto.


looks like ya got some good info while i was peckin this out and multitaskin

 

[rsplante]

...Did you chamber check your rounds in the actual gun barrel? You might check that the barrel has a forcing cone cut in it. BarSto delivers some of them short chambered and some smiths miss it.

How do I know if it has a "forcing cone"? Visually, it appears to have a sharp transition between the feed ramp and the chamber, nothing on the sides, and on the top there appears to be a slight taper over a 0.05" length axially.

 

[918v]

Bar-Sto chambers are tight. But if your loaded rounds drop in/out freely then it's not your crimp.

FTF malfunctions are caused by a number of things: Limp Wristing, insufficient recoil, too strong of a recoil spring, weak mag springs, feed geometry, etc. why do you think Glock had to hog out that chamber to make the gun reliable? In your case, everything has to be perfect in order for the gun to run. Retrace your steps.

Will it feed dummy rounds? Have you checked?
Is your load powerful enough?
Are you locking your wrists when shooting? This isn't a steel frame pistol, all the weight is in the top end, you must lock your wrists. Factory ammo generally overcomes the Limp Wristing with generous recoil. But you don't have that with target loads on the verge of not running at all.

As far as crimping goes, removing the bell is sufficient. If that round dies not chamber you have other issues.

 

[rsplante]

First check that chamber. Remove barrel, drop a fired empty in the chamber, then a loaded round...compare. If they are equal, you are likely fine. Next makes sure your OAL is not over 1.135". If it is, especially with the plated bullets, they can hang and induce feed problems.

If those are all good, then it is probably a fit issue of the barrel. Over-crimp plated bullets and you get another set of problems.

I do not currently have any fired empties that I know are my own. All the ones I picked up today were mixed with others, and all of the ones I know to be mine, from practice sessions, have been processed. All of the loaded rounds, including the ones that failed to feed, easily drop free of the chamber. I did notice that there was some hesitation to enter my doublealpha headspace gauge. Unless I dropped them in vertically, they hung up until tapped on the side. I understand that sammi specifies .421-.423. I tried .418 and they dropped into the headspace guage 95% of the time, even from an angle. How do you know if you are over-crimping? (and can .003 be considered overcrimping?)

 

[wakajawaka]

Throat or Leade
Transition between end of chamber and start of rifling. Rifling may also be cut away slightly.
Forcing cone is usually used to describe revolver barrels.

 

[rsplante]

the way i had it explained to me was, casemouth should feel smooth when you run your finger across it.i was concerned as well b/c i got some plated bullets i run. i did a accuracy test with no crimp , what i perceived as smooth/correct and finally excessive crimp 20 rds each.

What # recoil spring are you using Answ: 2#

Smooth was what I generally heard from fellow competitors today. The rounds that I just finished crimping to .418 feel pretty smooth. I am using a 2# recoil spring.

 

[OF&B]

As Wakajawaka posted, including the terminology

What's missing from a short chambered barrel is the ramp or taper on the ends of the rifling.

The mouth of the case must also catch on the end of the chamber he's pictured. Smooth bullets sound good, but they're not designed to be that way. Feel a factory round, they feed fine.

What pf are you loaded to? It takes ~130 to keep a Glock running reliably, even with 11-12# recoil springs.

 

[rsplante]

Throat or Leade
Transition between end of chamber and start of rifling. Rifling may also be cut away slightly.
Forcing cone is usually used to describe revolver barrels.

Ahaa! No, my mk 1 eyeballs do not detect any forcing cone; however, all of the FTFs I experienced were not a matter of failing to go into battery, but failing to even enter the chamber. i.e. the bullet was still .4 inches away from the end of the chamber. I might be wrong, but I don't think this is currently an issue. Should I contact BarSto about that anyway?

 

[rsplante]

By the way, that's a good looking picture. How do you actually post pictures to this site?

 

[rsplante]

Bar-Sto chambers are tight. But if your loaded rounds drop in/out freely then it's not your crimp.

FTF malfunctions are caused by a number of things: Limp Wristing, insufficient recoil, too strong of a recoil spring, weak mag springs, feed geometry, etc. why do you think Glock had to hog out that chamber to make the gun reliable? In your case, everything has to be perfect in order for the gun to run. Retrace your steps.

Will it feed dummy rounds? Have you checked?
Is your load powerful enough?
Are you locking your wrists when shooting? This isn't a steel frame pistol, all the weight is in the top end, you must lock your wrists. Factory ammo generally overcomes the Limp Wristing with generous recoil. But you don't have that with target loads on the verge of not running at all.

As far as crimping goes, removing the bell is sufficient. If that round dies not chamber you have other issues.

You could have something there. I believe I have a pretty good grip on the gun (despite being chronologically gifted, I still bench 225), but I loaded the rounds to just barely make Major (889fps average with an Oehler 35p and a 180 gr pill.) Should I be loading the same as factory rounds?

 

[17874]

Crimp it to SAAMI spec. Google
.40 S&W SAAMI spec and you will get a drawing with all the specs. Important not to Overcrimp though as it head spaces off the case rim.

 

[wakajawaka]

By the way, that's a good looking picture. How do you actually post pictures to this site?

First, the picture has to be hosted. Uploaded to a site like photo bucket.
The link is copied and pasted in the reply with

following at the end.

If you hit the reply with quote button on a post with a photo in it, you'll see it in the quote.

 

[918v]

You could have something there. I believe I have a pretty good grip on the gun (despite being chronologically gifted, I still bench 225), but I loaded the rounds to just barely make Major (889fps average with an Oehler 35p and a 180 gr pill.) Should I be loading the same as factory rounds?

No. Major PF is strong enough.

Another issue might be your chamber. It is tight. If you are reloading Glocked brass, your sizer die might not be sizing the base small enough and that's where its binding. Take the offending rounds and see where they're binding. You night need a Lee "U" die. It has an undersized carbide sizer ring.

 

[Wildboarem]

Question 1: can you lightly debut just that outside Edge, not enough to keep it from head spacing off the case Mouth?

I know my Lone Wolf barrel wasn't a barsto, but I had to smooth/ polish / shape the Chamber/ feed ramp. I had the same issue with Ftf. I had to round the feed ramp chamber transition, not as much as a factory Glock but some. I would remove barrel and push a round into the chamber with finger tension using the feed ramps angle until rounds would chamber. Polish more, try to slide into chamber and repeat until the rounds were chambering smoothly by hand.

I also will fl size a case and put into my seater die as a dummy, set die to just touch rim (crimp) and slowly work die in, measure, adjust die, measure. It is a lot easier to see how much crimp and to measure without a bullet seated. On e the die is set with a light crimp, load up 1 and test by hand. I found pushing a round into the chamber with my thumb really shows how smoothly a round will chamber. Anyhow, it's what has worked for me.

 

[rsplante]

No. Major PF is strong enough.

Another issue might be your chamber. It is tight. If you are reloading Glocked brass, your sizer die might not be sizing the base small enough and that's where its binding. Take the offending rounds and see where they're binding. You night need a Lee "U" die. It has an undersized carbide sizer ring.

Good point. I had not said, so you had no way of knowing, but I routinely run all used brass through a Redding G-Rx Push Through Sizing Die G-Rx Carbide Die Set | Redding Reloading Equipment: reloading equipment for rifles, handguns, pistols, revolvers and SAECO bullet casting equipment, so that can be ruled out.

 

[918v]

R u crimping using a separate die? If so, add crimp in 1/64 turn increments until the offending rounds drop in freely.

 

[bigedp51]

The taper crimp diameter should be no smaller than .001 to .002 than the normal diameter of the case after the bullet is seated. This is very critical with plated bullets because over crimping can damage the plating on the bullet and screw up accuracy.

The taper crimp is "NOT" designed to hold the bullet in place, it is just streamlining to help the cartridge feed into the chamber.

Below, a roll crimp "bites" into the bullet, a taper crimp gets rid of the case mouth flair and streamlines the case to aid feeding, but still allows the case to headspace on the mouth.

How to determine Max OAL for a CZ Pistol (or any pistol)

How to determine Max OAL for a CZ Pistol

Brian Enos's Forums... Maku mozo!

 

[ZombieMonkey]

You've already gotten some pretty good advice, crimp enough to remove the bell to the point where you can no longer feel a rough edge, should feel smooth. You can chamber check in your barrel or with a chamber check die. Do a number of rounds making sure that they all drop in smoothly and they all drop out smoothly. If anything hangs, crimp a bit more.

I shoot a lot of Rainier and Berry's plated bullets through my G22 and G27, they devour them all very well as long as you've got the crimp set properly.

 

[OF&B]

No. Major PF is strong enough.

Another issue might be your chamber. It is tight. If you are reloading Glocked brass, your sizer die might not be sizing the base small enough and that's where its binding. Take the offending rounds and see where they're binding. You night need a Lee "U" die. It has an undersized carbide sizer ring.

^This^. With Major PF your recoil spring is probably too light. Maybe 14# minimum and it should run on the stock one. I also like these. EGW U die made by Lee. It helps. Range brass is a reality for most action pistol guys.

If there is no leade in your barrel, it's the gunsmiths fault not Barsto's. Barsto does it on purpose because they don't know the final length the gunsmith is going to leave the hood at the back of the barrel.

If you disassemble your gun and check the barrel for peening and scrap marks there may be clues there. Particularly stuff around the lug on the bottom of the barrel that cams it in and out of battery. New Glocks don't always play nice with aftermarket stainless barrels. They almost always break in fine with their original tenifer parts. Mine was pretty beat before I started modifying it.

Simulating the ftf and taking a picture would help us as well.

 

[flashhole]

What specific bullet are you using? The RNFP has no step. From the pictures on the Ranier website, the flat point and hollow point appear to have a step. If you are using one of those bullets make sure you are seating the bullets such that the step is flush to the rim of the case. I shoot bullets I cast myself from the Lee Truncated Cone mold. I have to seat flush to the step or I get feed problems.

 

[918v]

The above drawing is wrong.

The above description of a taper crimp shows the bullet sitting in the case with air space between the case wall and the bullet shank. The case mouth is pressed against the bullet.

This is completely wrong. In reality is no air space between the case wall and the bullet. The case wall has a firm grip on the bullet due to case tension. The taper crimp looks just like a roll crimp except the radius of the curve is much larger so it looks like a taper instead of a roll.

Of you look inside both dies the only difference is the angle of the internal taper at the very end.

 

[427Cobra]

I crimp to my 40s to .421 for a factory G35 barrel, accuracy is good, feed is flawless, I put a 15lb recoil spring in because I shoot minor PF ammo at 127k, for any brass not fired in your current chamber I recommend you size them with a Lee Bulge Buster, it's an attachment to the LeeFCD, DO NOT, I repeat DO NOT use the crimping portion of the Lee Factory Crimp Die, throw it away, the LFCD will make all ammo(pistol) feed flawlessly at the great expense of accuracy, reason why is the carbide sizing ring resizes the bullet as it passes through in/out, the FCD with BB on it is a 35 dollar version of the Redding Carbide GRX.

 

[bigedp51]

The above drawing is wrong.

The above description of a taper crimp shows the bullet sitting in the case with air space between the case wall and the bullet shank. The case mouth is pressed against the bullet.

This is completely wrong. In reality is no air space between the case wall and the bullet. The case wall has a firm grip on the bullet due to case tension. The taper crimp looks just like a roll crimp except the radius of the curve is much larger so it looks like a taper instead of a roll.

Of you look inside both dies the only difference is the angle of the internal taper at the very end.

Dear 918v

While you are "technically" correct, the drawing depicts the types of crimps and not the grip of the case on the bullet. If you had bothered to look to the left at the entire cartridge you would have seen the case walls gripping the bullet. I found the drawing online and wrongfully assumed an "experienced" reloader would not think that the bullet would float or levitate inside the case while waiting to be tapered crimped.

I also highly recommend that you do "NOT" quit your day job thinking you will ever make it as an artist or god forbid an art critic.

Below showing off my ability to draw a straight line and appease your bloodthirsty quest for artistic perfection is the perfect taper crimp .001 to .002 smaller than case diameter.

If my above modified drawing crimps your style the drawing below should satisfy the most ardent crimping experts.

And last but not least the picture is worth a thousand words crimp.

Yours truly, bigedp51 anxiously awaiting your "artistic" reply. (I hope you can type better than you can draw)

Have a nice day, and may all your reloading dies rust.

 

[ZombieMonkey]

bigedp51's picture is spot on, obviously there is no gap, but it properly displays what each type of crimp is doing and what it should look like in application. It is 100% appropriate for this tread.

 

[918v]

Dear 918v

While you are "technically" correct, the drawing depicts the types of crimps and not the grip of the case on the bullet. If you had bothered to look to the left at the entire cartridge you would have seen the case walls gripping the bullet. I found the drawing online and wrongfully assumed an "experienced" reloader would not think that the bullet would float or levitate inside the case while waiting to be tapered crimped.

I also highly recommend that you do "NOT" quit your day job thinking you will ever make it as an artist or god forbid an art critic.

Below showing off my ability to draw a straight line and appease your bloodthirsty quest for artistic perfection is the perfect taper crimp .001 to .002 smaller than case diameter.

If my above modified drawing crimps your style the drawing below should satisfy the most ardent crimping experts.

And last but not least the picture is worth a thousand words crimp.

Yours truly, bigedp51 anxiously awaiting your "artistic" reply. (I hope you can type better than you can draw)

Have a nice day, and may all your reloading dies rust.

Form over substance, just like a leftist.

 

[rsplante]

What specific bullet are you using? The RNFP has no step. From the pictures on the Ranier website, the flat point and hollow point appear to have a step. If you are using one of those bullets make sure you are seating the bullets such that the step is flush to the rim of the case. I shoot bullets I cast myself from the Lee Truncated Cone mold. I have to seat flush to the step or I get feed problems.

I will keep that in mind if my problem reappears. Yesterday afternoon, I crimped to .418" as someone at the range recommended and then redeveloped my load (I wanted to make sure I was not going to get a Kaboom!). At the lowest level, after the first round at 613 fps (5.32gn HS-6) the second round failed to feed. I thought, guess I still have a problem. I worked my way up to 1100 fps (8.21gn HS-6) over 25 rounds in five steps and never had another hiccup. I shot another 20 of my competition rounds (recrimped to .418") at 950 fps with no problems (yes, for anyone that remembers, this is an average of 60fps faster than what I originally developed, I'm guessing that that is a result of the extra crimp causing the development of a little more pressure prior to the case releasing the bullet, resulting in my resorting to redevelopment of the load.) These have an average OAL of 1.128" with about 0.04" to the step.

At this point I have to admit to being stupid. I had carefully zeroed my Trijicon RMR sight, with commercial ammo. Yesterday I noticed that my competition ammo, which was downloaded to barely make Major PF, was hitting about 4" low. I guess that might account for the No-Shoots! (both of which were 1" below the top of the no-shoot)

YEP, if my math is correct, that explains it. ~45' at 1150 fps = .0391 sec. 45' at 950 fps = .0473 sec or .0082 sec longer. .0082 x 32fps/s (gravity) approx equals .2624', or 3.15"

 

[rsplante]

427Cobra, The reason I asked wakajawaka what he used for photos, is because over the years I vaguely remembered your "STOP USING PHOTOBUCKET!". Could you please explain what is objectionable to you about Photobucket (Am I allowed to hijack my own thread? If not, I'll just blame it on my ADHD.)

 

[427Cobra]

I hate seeing PB little banners saying look whose popular or photo nowhere to be found, it seems to slowed down but I still don't like it.

 

[anarchist]

Are you using a case gauge? I use the Lee Factory Crimp die and a Wilson case gauge. Keep adjusting the die down until your rounds will drop into the case gauge freely. Done deal. Since the round headspaces on the case mouth, too much crimp is a bad thing. This is my KISS approach.


Sent from my iPad using Tapatalk

 

[rsplante]

Are you using a case gauge? I use the Lee Factory Crimp die and a Wilson case gauge. Keep adjusting the die down until your rounds will drop into the case gauge freely. Done deal. Since the round headspaces on the case mouth, too much crimp is a bad thing. This is my KISS approach.


Sent from my iPad using Tapatalk

Nah, it's not a matter of fitting into the chamber. It does that easily, and drops out easily also. It was having a hard time making the turn from ascending the feed ramp to entering the chamber. But to answer your question, I have both a Dillon 40 S&W headspace gage, and a Doublealpha 40 S&W x 20 headspace gage.