100% Straight Cases - 40S&W

[Dwight Springthorpe]

I have a Tanf Limited 40S&W and am having some problems with used brass. My limited likes to nose dive the rounds when using the 21 round mags with reloaded ammo. I understand that is not uncommon.

I have tried different OAL from 1.135 to 1.200" I read on this forum that 1.225" may be a OAL that helps, but I have not run any cases with that OAL to test. I also have read many of the forum entries that say you need new brass or to be sure that they are 100% straight. I believe the "gizmo" tool can help may them straight, so I have emailed for some info on the gimzo that helps you get the cases this way, but I do not have it. I also have the U Lee die.

However, I think I am missing something...

After I deprime the case using the Lee U die, the rim is 0.420", the base of the case is 0.422", middle of the case is 0.415" and the neck is 0.415". after I seat the bullet and crimp it, the neck expands to 0.421" (which is correct, the brass is 0.0105" thick and the bullet .400").

So, when all is done, I have an hour glass shaped cartridge (rim measure does not change and is left out) 0.422 - 0.415 - 0.421.

I thought I understood, the need for the U (undersized) Lee die, but that seems to be counter productive as it is now 0.005 smaller that what is desired for a 100% straight case. 0.422 - 0.415 - 0.415

What is the secret that I am missing?

Do I need to use the gizmo (stand-alone press) and then just deprime the cases using the 650xl? Does the gizmo leave the case straight at 0.415 - 0.415 - 0.415?

Would that not mean that I would end up with a cartridge begin 0.415 - 0.420 - 0.420"? This is more like a wedge than straight.

If anyone could help shed some light on where I am missing it wether it be equipment, procedures or the loose nut behind the trigger, I would appreciate some guidance in getting my limited to feed right.

Thanks for your help,

Dwight

[DarthMuffin]

Have you tried tweaking your magazine feed lips? I have in my notes from a post in this forum that .395" is recommended, both front and rear.

You may also check the video on Henning's site, he briefly shows how to tweak the spring (adjusting the top coil) for best performance.

That and using a U die (mine also gives the hourglass measurements like you mentioned) and loading to 1.175 do it for me. Although I still don't load to 21 unless there's a need for it on the stage. 20 will do it 99% of the time.

It also helps to load the mags carefully and be sure to seat each round as far back as possible. I use an UPLULA and hold the round in place while disengaging the "tounge". Every few rounds tap the mag to seat them too.

[Dwight Springthorpe]

Have you tried tweaking your magazine feed lips? I have in my notes from a post in this forum that .395" is recommended, both front and rear.

You may also check the video on Henning's site, he briefly shows how to tweak the spring (adjusting the top coil) for best performance.

That and using a U die (mine also gives the hourglass measurements like you mentioned) and loading to 1.175 do it for me. Although I still don't load to 21 unless there's a need for it on the stage. 20 will do it 99% of the time.

It also helps to load the mags carefully and be sure to seat each round as far back as possible. I use an UPLULA and hold the round in place while disengaging the "tounge". Every few rounds tap the mag to seat them too.

I measured them again and I have 0.395" +/- 0.001" on the feed lips. I thought I had done that, but I had not checked in the last week.

I do use a simple loader and I follow the video on the website for how to load the mags, so 21 usually go in with only a little effort and a lot of tapping.

I will check the Henning site for the tuning video.

Thanks for the ideas!!

Dwight

[Seth]

Dwight,

I ran with you at SWGC a couple of months ago and watched your problems. At the time I remember thinking it was ammo related.... Have you case gauged your ammo? How about pulling the barrel and checking with it?

My offer to try some different ammo stands, if you want next month. I'm pretty anal retentive about my reloads and will be 100% certain that they're completely in spec.

Seth

Edited April 15, 2009 by Seth

[benny hill]

Make sure your crimp is .418 for jacketed & .416 for lead to avoid bullet push back & stall out.

[John Dunn]

The hour glass shape is OK, in fact it is good as it will help defeat bullet setback during the feeding process which could lead to high pressure. This is the main reason I use it, not for the Glock bulge, although it works well for that, too.

If you are not using one already I'd suggest a Redding competition seating die to seat the bullets straight. This made a significant improvement in the "straightness of my ammo.

As above, gage or chamber check your ammo, then look at the guns and mags.

[CHA-LEE]

Follow the reccomendations in the below thread to solve the nose dive issues. Three key things are 1.225 OAL, Gizmo Sized Cases to .415, and set the magazine feed lips to .385. If you do this you will have ZERO feed problems and can load to 21 rounds in a mag easily. Me and three other EAA shooters here in Colorado have been using this setup for months and many thousands of rounds now with zero issues. It simply works when you set it up this way. Believe me, I have tried EVERYTHING else as well to try and solve the nose dive issues.

http://www.brianenos.com/forums/index.php?...c=76873&hl=

[CHA-LEE]

The only other solution is to shoot brand new brass. If you are going the new brass rout then Starline is really good stuff. I don't know about you guys, but its beyond my budget to shoot brand new brass only once. Its a LOT cheaper to use some elbow grease and run the cases through the Gizmo Resizer to make any brass feed perfectly in my gun.

[Dwight Springthorpe]

Everyone;

THANKS for all of the ideas and information.

I don't have a case gage for the 40S&W, but I did pull the barrel and check for case fit. All looked OK, but I will find me a gage to be sure.

Crimp. My crimp is at 0.421" with JHP. I will see if I can tighten it up a bit. Since I started reloading for the limited, I have not had any push backs.

Seth; Yes, I was having ammo issues at SWGC. I was using a bunch of reloads and they were pushing back into the case a long way. I have been trying a couple of different bullets, but nothing has made a big differnce.

I do not have a competetion seater yet, I have been trying to find one, but I have not yet been able to hook one up.

I have also been trying to get a case gizmo to try to see if that will help.

I also have adjusted the springs as hinted to on Henning's website.

Right now my last set of trails was 1.226" OAL, with a crimp of 0.421" and a mid case of 0.416". This is looking better, but I still seem to get a nose dive when I am working with them. This load has not been tested fully yet.

Thanks again and if you think of more, PLEASE let me know.

Dwight

[Ridgerunnr]

I have had only a few feed problems. I run an undersized die, 1.180 OAL lead bullets. Crimp is where it should be and i get a minimal hour glass shape to the brass..once fired range brass.

The only problem I see is the mag lips are not at the measurements mentioned above. WHat is the easiest way to

narrow them without doing any damage to the mag surface???

[al503]

I don't have a case gage for the 40S&W, but I did pull the barrel and check for case fit. All looked OK, but I will find me a gage to be sure.

The barrel is the best case gauge. If you pull the bbl each time, don't worry about buying a gauge.

Crimp. My crimp is at 0.421" with JHP. I will see if I can tighten it up a bit. Since I started reloading for the limited, I have not had any push backs.

This is how I figure crimp. Measure the loaded round down a further down on the bullet (where it is unaffected by the crimp). Try to get within +- .0005" of that figure around the lip of the case after it's crimped.

[Seth]

Dwight,

I have a case gauge you're welcome to... I'll put it in the mail tomorrow if you want it, I'll get it at another match. The case gauge IS tighter than my barrels, so if it passes that, the ammo works.

Dillon shows the Redding Comp. Die:

http://www.dillonprecision.com/#/content/p...ol_Seating_Dies

Seth

Edited April 16, 2009 by Seth

[Dwight Springthorpe]

Dwight,

I have a case gauge you're welcome to... I'll put it in the mail tomorrow if you want it, I'll get it at another match. The case gauge IS tighter than my barrels, so if it passes that, the ammo works.

Dillon shows the Redding Comp. Die:

http://www.dillonprecision.com/#/content/p...ol_Seating_Dies

Seth

Seth; Thanks for the offer. I just ordered the gage and the die from Dillon. I hope it will made a difference.

Dwight

[Front Man]

Make sure your crimp is .418 for jacketed & .416 for lead to avoid bullet push back & stall out.

Benny,

I have been loading for over 15 years and crimp my cases so the bullet won't push back, but what is Stall Out?

FM

[heckle]

Another thing to keep an eye on is how clean your mags are one piece of dirt in a mag can cause a nose dive. When I drop a mag in the dirt I clean it before using it again.

I would not use the barrel as a case gauge the problem isn't the round going into the barrel its how tight they are stacked in the mag.

If your having trouble with nose dives than use Cha-Lee's formula. For anyone that doesn't have nosedive issues than do what works (if it aint broke don't fix it).

[Dwight Springthorpe]

Just an update on my progress, so that is might help anyone else that has simular issues.

The width of the magazine lips seems to have helped the nose-dive issue. I am now keeping them at 0.390” to 0.392” at the point of release. Since I made that change, and keeping the springs stretched at each cleaning and keeping the magazines very clean (wow that is a lot of things…) I have not seen the nose-dive issue.

But while trying different solutions to fix the nose-dive problem, I tried some very short rounds. The OAL of my load was down to 1.125” using Montana Gold 165gr JHP. Since I was also trying some Zero 165gr JHP and some Remington factory ammunition (1.127” OAL), I may have been too short for the gun. It seems that there was too much room in the magazine based on the short OAL. On more than one occasion yesterday, the round popped up and did not catch the top of the chamber. So it was pointing up or jammed by not going in the chamber.

Lastly, I may have been getting poor feeding due to the recoil spring. Some of the issues I saw yesterday appear to have been due to a weak spring. I replaced it with what I believe to be a 12# spring.

With all of these corrections, today, I was able to get a short sucessful test today.

This is better than it has been doing. My current load is OAL: 1.200”, Montana Gold 165JHP, 6.1gr of VV340, estimated PF: 176, federal primer, all cases have been resized using the Gizmo that gets the fired brass to 0.415”, I use the Lee undersized die and I crimp to 0.420” at the top of the case. Also a 12# recoil spring.

So after doing ALL of the suggested items, I may have resolved my issue for now. Only time will tell.

Thank you to all that contributed help and suggestions.

Dwight