Case OAL when using Possum Hollow?

[Mike in CT]

As some of you may know I have just started to reload .223 after loading several thousand rounds of pistol.

My question tonight is that I bought the Possum Hollow trimmer that spaces off the case shoulder. It seems that I am getting a variance in OAL, is that due to the fact that the bottom portion of the case is different lengths and when I just trim from the shoulder I get the OAL variance?

If so, is that OK? and what is an acceptable range for OAL?

I want to use the Possum Hollow as I want to do bulk loading and a 'lathe' type case trimmer seems that it would get the OAL into a tighter tolerance but would take 3 or 4 times as long,

Thanks for all the help, hoping to get some loaded rounds for testing soon,

Mike

[Guest]

Are you resizing the case before doing the trimming? What are the actual measured variances you are seeing?

[Mike in CT]

Hello,

Yes I am full length resizing prior to trimming. I will run a couple dozen this afternoon and report the findings.

I am taking it slow with the rifle so I have not touched any brass for a few days.

More details to follow,

Mike

[Cotys]

I use the Possum Hollow on 270, 308 and 5.56. I've found it difficult to get the initial setting right where I want it. Once I get that set, it has worked well for me.

Let us know how much variation you are getting. Is this mixed brass? I usually run all Lake City or all Partizan at one time.

I use the drill mount and have threaded them to fit onto an RCBS case trimming station. You can see my first attempt in the rear - washers, bolt and J.B. Weld. The second two I drilled through the stem and threaded them.

Edited March 1, 2012 by Cotys

[Mike in CT]

It looks like the variations are coming from different headstamped brass. I sorted out 50 of LC headstamp, but variations on the actual stamp, and run them pas the Possum Hollow. I came up with a variance from 1.745 to 1.755 and it seemed that the longer ones all had the exact same headstamp.

Can I go ahead and load these?

I am loading for volume, not for match grade ammo. I will be using Montana Gold 55gr bullets.

I am thinking it would have been better to buy 1,000 rounds of brass rather than to scavenge up twice that much.

I guess the other option would be to go with a 'lathe' type trimmer like the lyman?

Thanks for the help,

Mike

[Guest]

1.745 - 1.755 is within spec, so you shouldn't have anything to worry about.

I just checked a handful trimmed on the Possum Hollow and they ranged from 1.751 to 1.756, and I wasn't particularly trying to be consistent as this batch is for general purpose use (with hornady or Montana Gold 55grainers). I've found that twisting the case as it is being trimmed helps a lot. When the trimming is done the sound of the trimmer and feel changes as I twist the case. I then lightly chamfer the inside and debur the outside. Also, I find that a spindle speed of about 800rpm works pretty good and leaves a clean edge. If I am loading for accuracy with premium bullets I'll usually do only a couple hundred at most, and will spend a little more time trimming which helps get better results. Also, be sure you are using enough lube on the cases during the sizing operation and are being consistent with that also, since the trimmer indexes off the case shoulder any inconsistencies in that area will affect the trimed length.

The PH trimmers works pretty well and I use them for .223 and .308 with good results, I'd recommend spending a little more time with it before tossing in the towel.

Edit: I meant to add that processing bulk .223 is a huge PIA no matter how you do it...unless you buy it pee-processed which actually sounds really good sometimes!

Edited March 2, 2012 by Bamboo

[Mike in CT]

Bamboo,

Thanks for the info.

Yeah, rifle is nothing like pistol.... Pistol = pick up brass, run through press, go shoot. Rifle... ARGH!!!

I did get the lube part down, I switched from Hornady to Lymann and used generously. I actually stood up all the cases and sprayed. Going to just try a backing sheet approach next to improve throughput.

Like most things this seems to have a steep learning curve but I think I am in sight of the top of the curve.

Back to the press!

Mike