Frankford arsenal case prep unit

[grizzly63]

So I bought this unit and have been using it to reload a few different calibers. The question I have is this spaces off of the shoulder so not all cases have the same overall length when trimmed. Is this a problem? I have not seen any accuracy problems. Only thing of note is it leaves some brass flakes in the inner neck. I just run a brush through the neck and it cleans them out. I use a final crimp die on almost everything I shoot and the length thing makes me wonder if I am developing different pressures? Prior to this I was using a Lee universal case trimmer which is a good unit but this case prep thing is much faster with the multiple tasks at hand.

 

[Addicting]

I doubt your going to notice the accuracy difference until you get out past 500 yards. I like those units but to me they are more for a mass produced shooter, not necessarily a accuracy shooter.

 

[grizzly63]

Funny you say that. I didn't buy one until I had an AR. One of my conflicting thoughts was you are trimming it off of the shoulder but all the other steps are off the base of the case.

 

[Millsworks]

After a few firings and trims they should all be awful close in over all length.
The real need to trim keeps the case neck from getting squeezed into the throat and excessively clamping down on the bullet.

The shoulder should be set back a consistent amount during the resizing process. Thus, keeping things consistent.

 

[coleslaw]

Some of what you are getting might also be differences in the thickness of the rim of the cartridge. That's my guess. I run the same system and have the same issue. Nothing of concern, but once in a while I get a real head scratcher, and on some of those (mostly Hornady brass) I can visually see that the thickness of the case rim itself can vary when compared to another cartridge. This will cause issues when measuring with your micrometer.

 

[Don Fischer]

I have a bunch of Frankford FA case's I used to load cast bullet's in my 30-06. After you trim there will be little brass trimmings inside the neck. That's what the neck reamer is for. Takes those out of inside and outside the neck, do not over do the trimming. If you do you'll find yourself splitting necks! The only military surplus cases I've had good accuracy with is Lake City cases. Best came with LC National Match cases, no year on the stamp. As much as all case's vary in weight, I suspect military case's vary more and guessing that is the reason normally. Military doesn't seem to care if their rifles don't fire 1/2" groups!