.40 Accuracy problems

[MFP4073]

I am currently loading .40 for USPSA competiton. I had a load worked up that I thought was working pretty good.

180gr. Rainier RNFP
5gr W-231
Winchester Case
Fed Primer
1.15 OAL

At 25-30 feet accuracy was about 4" groups. At one of the matches this winter there was some steel set up at greater distances (40-50 feet). I was having trouble hitting them. I shoot a lot of steel matches (with different guns than my IPSC gun) and usually do not have the degree of misses I experienced.

So, I checked the accuracy of the bullets at 50 feet and the group would not get tighter than 11" No wonder I was missing so much!

Decided to try Titegroup based on many recommendations.

Same bullet config but with 4.5 gr of TG.

Tested today crony at 170 PF. Accuracy was absolutely terrible, even at 25 feet. I mean groups of 16" at best!

Any recommendations? Is it the Rainiers? OAL? I know my crimp is not excessive.

Thanks in advance for any advice!

Matt...

 

[jhrosier]

Whitey,
WAG, sounds like an ignition problem.
Check that primers are fully seated in relatively clean pockets.
If the listed powders are slow burning, are you using a heavy enough load to ensure complete burning? Some slower powders only work well near maximum loads.
Jack

 

[Gammon]

As far as accuracy is concerned, I find that jacketed is the most accurate with hard cast lead a close second and plated a poor third. Not poor enough, however, to produce the groups you describe. I use WW 231 almost exclusively in .40 and have had pretty good luck with Rainier bullets.

Plated bullets are usually made with soft lead as the bullets are swaged into their shape prior to plating. My guess is that you are over crimping and reducing the diameter of the bullet to the point that it is not picking up a spin from the rifling. Back off on the crimping die and your groups should improve.

 

[Adam_MA]

Some good load info here..

http://home.columbus.rr.com/jmaass/ipscload.htm

As for your load, you may want to increase your powder a bit on the Titegroup. I load 180's with 4.7, and seat to 1.125

 

[GTOShootr]

I would bum some Montana Golds or Zeros from Paul or Pete and see if they work any different in your load. Also, try someone else's load or let someone else see if they have the same experience shooting your gun. The sights are tight, the Bo-Mar isn't broken?

I load to 1.15 too and need 4.8gr to get 170 pf out of my Shuemann barrel. 4.7 at 1.125 must be smokin, nice!

 

[Scrivener]

What are you using for a crimp die? I seat and crimp separately, using a Lee Final Crimp die on all my auto pistol ammo.

The FCD not only prevents over-crimping, but it resizes the entire cartridge, greatly reducing FTF's.

I also stopped using plated bullets. I now use poly-coated bullets, which are extremely clean and much cheaper.

 

[MFP4073]

Thanks for all of the feed back guys. I was getting frustrated with this.

10MM Dave gave it a go with my gun after bowling pins this past Sun and had the exact same results. Then we put some of his 200 gr loads through it that he uses in his Revo and we were right on the money. I figure if he experiences it, it has to be the loads. BTW my IPSC gun is a Para P-16 with many upgrades but a factory barrel.

Dan H. said that he and the guys at Harvard had the exact same experience last year with plated bullets. Citing that when loaded to major PF and running over 925 FPS the bullets distort or separate.

I am going to work up some jacketed bullets this week and see how it goes. Once I get my match load straightened away I am going to go back and see how accuracy is on the Rainiers loaded for steel. I suspect they will tighten up as I have been using Rainier 38's and 9's for steel for a few years and always had great results. Hence the reason for choosing them for IPSC.

I will post back with results. I better get one worked out soon 'cause the outdoor season is just around the corner!

Thanks again,
Matt...

 

[MFP4073]

Oh yea... I load on a Dillon 650 so seat and crimp are on separate stations.

-Matt..

 

[TonyD]

What are you using for a crimp die? I seat and crimp separately, using a Lee Final Crimp die on all my auto pistol ammo.

The FCD not only prevents over-crimping, but it resizes the entire cartridge, greatly reducing FTF's.

I also stopped using plated bullets. I now use poly-coated bullets, which are extremely clean and much cheaper.

What problems have you seen incure with over crimping?

 

[Scrivener]

What problems have you seen incure with over crimping?

1. Deformation of the bullet, with the obvious consequences;

2. Auto cartridges seat on the case mouth - overcrimping can cause the cartridge to go too far forward, with light strike problems resulting.

 

[TonyD]

1. Deformation of the bullet, with the obvious consequences;

2. Auto cartridges seat on the case mouth - overcrimping can cause the cartridge to go too far forward, with light strike problems resulting.

My conundrum is that I have a RCBS 4 station and I have to seat and crimp with the same die. 9mm I don't have to crimp because of the taper but .45 I have to. I have some .45 test loads ready to go but haven't had a chance to actually test them. I'm just looking for some possible problems and diagnostic tools.

 

[Adam_MA]

Tony,
I wouldn't be too concerned. I seat and crimp in the same stage with the same die as well. I have over crimped a couple of rounds getting things setup, and it was visually obvious that I had done so. You could see that the case was bulged out just below the crimp, the crimp bit into the bullet so much that the bullet was completely flush with the sides of the case, and a couple of rounds actually buckled the case walls. If you don't have a case gage, you can check by dropping them into the chamber of your barrel, and make sure they go in.

Adam

 

[TonyD]

Tony,
I wouldn't be too concerned. I seat and crimp in the same stage with the same die as well. I have over crimped a couple of rounds getting things setup, and it was visually obvious that I had done so. You could see that the case was bulged out just below the crimp, the crimp bit into the bullet so much that the bullet was completely flush with the sides of the case, and a couple of rounds actually buckled the case walls. If you don't have a case gage, you can check by dropping them into the chamber of your barrel, and make sure they go in.

Adam

They're not bulged and mic at .475 (.001 under spec).

I might also add I use RCBS roll crimp dies.

 

[Scrivener]

My conundrum is that I have a RCBS 4 station and I have to seat and crimp with the same die.

Why?

My Dillons are 4-station presses and I seat and crimp separately for all pistol calibers.

Station 1: Size, de/reprime

Station 2: Bell case, throw powder charge

Station 3: Seat bullet

Station 4: Taper crimp w/Lee FCD

.38 Super, .40 or .45; all are reloaded as above.

No crimping issues whatsoever.

 

[TonyD]

Why?

My Dillons are 4-station presses and I seat and crimp separately for all pistol calibers.

Station 1: Size, de/reprime

Station 2: Bell case, throw powder charge

Station 3: Seat bullet

Station 4: Taper crimp w/Lee FCD

.38 Super, .40 or .45; all are reloaded as above.

No crimping issues whatsoever.

Because station 2 bells and station 3 is case activated powder drop.

 

[adweisbe]

Because station 2 bells and station 3 is case activated powder drop.

Time to get a powder through expander die

 

[TonyD]

Time to get a powder through expander die

I wonder if they work with a Uniflow or is that something Dillon specific?

 

[adweisbe]

I wonder if they work with a Uniflow or is that something Dillon specific?

Lee and Hornady also support it. I am going to guess that it probably doesn't because the belling has to be supported by the powder measure. If the powder measure uses a case activated linkage it might not provide any resistance to the drop tube that is supposed to bell the case mouth.

 

[Scrivener]

Because station 2 bells and station 3 is case activated powder drop.

A most unfortunate misuse of limited space. I take it this is an old design.

 

[TonyD]

A most unfortunate misuse of limited space. I take it this is an old design.

Yes. The 4X4 Auto discontinued around '90 I believe. It was all free so I work with what I have.

 

[adweisbe]

Technically the Lee FCD (and full length resizing) may not necessary if you sort your brass by headstamp and generation and ensure they have a uniform length. The cartridges may fail to gauge because case length varies along with the resulting crimp even with a single die setting. If they still fail to gauge the bullets may be oversize or you are using too much crimp or you need to get the chamber finish reamed.

There is nothing wrong with crimping and seating in the same step. It just links the two die adjustments together which can annoying.

 

[TonyD]

Technically the Lee FCD may not necessary if you sort your brass by headstamp and generation and ensure they have a uniform length. The cartridges may fail to gauge because case length varies along with the resulting crimp even with a single die setting. If they still fail to gauge the bullets may be oversize or you are using too much crimp or you need to get the chamber finish reamed.

The fifty test rounds were all assorted brass. All mic'ed .001" less than spec with no over crimp problems that I can see.

 

[Scrivener]

Yes. The 4X4 Auto discontinued around '90 I believe. It was all free so I work with what I have.

You certainly can't beat the price.

That said, if you're looking to do some serious volume, get a Hornady or a Dillon. If necessary, sell the 4x4 to get the seed money!

Note also the 1,000 free bullets if you buy a new LNL.

 

[TonyD]

You certainly can't beat the price.

That said, if you're looking to do some serious volume, get a Hornady or a Dillon. If necessary, sell the 4x4 to get the seed money!

Note also the 1,000 free bullets if you buy a new LNL.

I'll not sell this as long as RCBS continues to support me. If I bought new for an additional press, I'd be looking hard at Hornady.

Taking my time and watching all critical procedures, I get about 350 an hour. The slow down is reloading the primer tube.

 

[Scrivener]

Taking my time and watching all critical procedures, I get about 350 an hour. The slow down is reloading the primer tube.

Well, that's twice as fast as I can on the 550. I don't know how people get that sort of output. I check my powder charges and cartridge length!

 

[Gammon]

Well, that's twice as fast as I can on the 550. I don't know how people get that sort of output. I check my powder charges and cartridge length!

400 rounds per hour is an easy pace for the 550.

 

[Gammon]

1. Deformation of the bullet, with the obvious consequences;

2. Auto cartridges seat on the case mouth - overcrimping can cause the cartridge to go too far forward, with light strike problems resulting.

Most semi auto cases headspace on the extractor because few are long enough to reach the end of the chamber. Because of this, you can actually roll crimp semi auto rounds with no ill effects, although I don't recommend it.

 

[TonyD]

Well, that's twice as fast as I can on the 550. I don't know how people get that sort of output. I check my powder charges and cartridge length!

I check all this when I set it up. I look into every case before setting the bullet for any obvious powder variance then re-verify length on two or three after each fifty.

 

[Adam_MA]

I check all this when I set it up. I look into every case before setting the bullet for any obvious powder variance then re-verify length on two or three after each fifty.

That's my process as well.

 

[MFP4073]

Problem Solved!

I wanted to post this on Sun when I got home from the club but... today is the first time I have been able to sit down.

I worked up three new IPSC loads to test using Montana Gold JHP 180gr. Here is the config.

MG 180gr JHP .40
Winchester Case
Federal Primer
4.5 gr , 4.7gr, and 4.9gr Titegroup
1.175 OAL

Here is the data:
4.5gr TG: Hi= 916 FPS , Lo=884, Avg= 901 PF= 162.2
4.7gr TG: Hi= 951 FPS, Lo=928, Avg= 939 PF=169.1
4.9gr TG: Hi 985 FPS, Lo=965, Avg= 972 PF=175.1

Good news! the group tightened right up and all were about equal in accuracy. I was able to get 3" groups with one or two filers (most likely me jerking the trigger) from each load shooting 10 rounds at the full lenght of the MRA loeb range - about 75' - 80'.

Recoil was "stiff" but not unmanageable as is to be expected with a major PF .40 out of a limited gun. Although I thought 4.9 was pretty explosive.

I will continue to do a little more testing with the load and perhaps the recoil spring in the gun but I am happy to be in the ball park in time for the outdoor matches this season.

Thanks to all who provided feedback.
Especially Dan from HAS- your information about your experiences with the same problem was helpful.

-627