416 Rigby case length criticality

[Ozone]

I'm new to the website - so thank you for having me. I'm not new to reloading but I'm new to reloading 416 Rigby and crimping. I have reloaded several calibers over the years but I have never crimped my cartridges. My mentors in reloading were bench rest shooters and very anal about all aspects of the process and the finished cartridge.

That said, I need to know if I'm being overly critical for the big 416. After shooting new cases once, I'm finding that many of them are less than 2.8975". I would like to keep all brass between 2.898 and 2.900 ( due to my trained attention to such dimensions) I plan on crimping on the cannilure of the 400 gr. A Frame bullet.

Am I being to critical of the case length ? Can I use brass that measures 2.897 or less with the crimp and expect consistent performance?

I plan to use a separate seating die to perform the crimping operation. All dies are RCBS.

I don't expect the 416 to shoot less than MOA groups but I do want acceptable accuracy.

I would normally fire-form the new brass a second time to stretch the neck length then full length resize and trim to my target brass length. This can be a costly process in the 416.

Thanks for your feedback.

 

[Clayton]

Know what you're saying about the BR Shooters. Was there myself for a few years.

Case length on the .416 shouldn't be any more critical than any other round you are used to loading for. The .0005" is minimal.

Others who do load for the Rigby will be able to give you hands on advice.

Good luck.

 

[PHOENIX PHIL]

I personally like to seat my bullet to same COAL everytime. I also like to crimp my rounds. As such the trim length of the brass is important if your crimping into the cannelure. I would trim them the same length and to allow crimping. That said your tolerance of +/-0.001" seems challenging and a bit excessive as the cannelure on the A-Frames is a bit wider than that.

 

[CAustin]

Welcome to AH sir!

 

[Rule 303]

I know, I am a bit late replying in this thread. I use the Lee factory crimp die on my 416Rigby. Case length is not as critical as other methods and is easily adjusted. The only draw back is the Lee 416Rigby factory crimp die is a special order and fit in the bigger thread than the standard dies. I have heard that others had a gunsmith open up the 416Rem Factory crimp to take the Rigby case.

 

[ChrisG]

I don't think you need to be super critical of length of the brass. The reality is, while medium bores on up (bigger than .366) are inherently very accurate due to the fact that a fouled bore has less of an effect percentage-wise on the bore condition at firing, very VERY few of us can repeatedly shoot them as well as they mechanically can shoot. In fact, they are very rarely benchrested, only to check zero, because of the abuse you take sitting. It is even worse shooting prone. I have a .375 H&H and a .416 Ruger and I wouldn't dream of shooting them prone. Some guys... Looking at you @matt85... seem to have an inhuman resitance to the effects of recoil. I don't. So I shoot mine from field positions and I doubt if I'm going to gain much even if I trimmed my brass to all within 0.01" of each other. As long as they are under SAAMI OAL, fit in the magazine and all crimp in the cannelure, I don't worry about it. I can hit a pie plate from 150 yards from field positions using the sling and probably a little better with an improvised rest or shooting sticks. But I never shoot enough to get my bench groups down to .5MOA because it just isn't necessary as I will not be shooting over 300 yards.

I say all that to say that 0.0005" isn't going to matter a hill of beans compared to your ability to shoot it well. Just my two cents but... what I look for when I am loading the bigger calibers is that all the crimps are the same (the Lee FCD is a good suggestions) and the bullets won't set back. Measure your powder charges accurately and have fun! The Rigby is going to be a very forgiving cartridge because it is so HUGE. Leave mic-ing the cases to .0001" for when loading 6.5 creedmore and shooting 500-1000 yards at paper. Thats where you'll see a big difference.

 

[Grumulkin]

That said, I need to know if I'm being overly critical for the big 416. After shooting new cases once, I'm finding that many of them are less than 2.8975". I would like to keep all brass between 2.898 and 2.900 ( due to my trained attention to such dimensions) I plan on crimping on the cannilure of the 400 gr. A Frame bullet.

Am I being to critical of the case length ? Can I use brass that measures 2.897 or less with the crimp and expect consistent performance?

I plan to use a separate seating die to perform the crimping operation. All dies are RCBS.

I don't expect the 416 to shoot less than MOA groups but I do want acceptable accuracy.

I would normally fire-form the new brass a second time to stretch the neck length then full length resize and trim to my target brass length. This can be a costly process in the 416.

I have a few comments:

1. When I resize brass, I trim only those pieces that are too long unless a high percentage are too long in which case I trim all.

2. The Lee Factory Crimp Die works great. In my 458 Lott, the crimp function on my Hornady die works fine. In my 378 Weatherby I couldn't get enough of a crimp to prevent bullets from moving with a regular die without collapsing the case. A Lee Factory Crimp Die solved that problem.

3. Why don't you expect the 416 to shoot less than MOA groups? I think it could very well be capable of less than MOA groups.

4. Why in the world do you fire form new brass? What a waste of time for no gain of anything. I generally do NOTHING to new brass except load it and I'll bet the accuracy you get from your efforts is no better and perhaps worse than if you just loaded and shot your new brass.