Case length

[Robin]

I'm getting stuff ready for this winters reloading and thought with the third reloading of this batch in 6.8 SPC cases (SSA) it might be time to trim them. My book, Nosler, shows only one dimension for case length, no minimum and maximum. My cases are already below the dimension shown. I am not trying to make little magnums, I just want to wring out the very best consistent accuracy possible for my reloading efforts and to my way of thinking, trimming them all to the exact same length would be a big part of that. If there is a section in the book that discusses this I missed it, several times. Any thoughts on this would be greatly appreciated.
Robin

 

[kev74]

It doesn't seem like there's a lot of published info in the 6.8 SPC out there.

Just a guess on my part, but if you trim everything to the shortest length you have, you can get the uniformity you're looking for without going into uncharted territory.

Some interesting reading...

https://68forums.com/forums/showthread.php?102769-6-8-SPC-II-Minimum-Case-Length

6.8mm SPC FAQ & Load Data Part III - Page 1 - AR15.COM

https://68forums.com/forums/showthread.php?27129-What-is-the-trim-length-for-6-8SPC-II-chambers

 

[JamieZ]

Case length 1.676 and being that I have an AR my magazines only allow a COL of 2.26

 

[JamieZ]

Hope this will help you,,,,I run my cases everytime through this before reloading. Sometimes it trims when needed and other times it doesnt. You just set it up for the length you want and thats it. Never have to mess with it again. My cases are always the right length. Takes about 2 seconds a case.
Little Crow Gunworks World's Finest Trimmer 6.8mm - MPN: WFT6.8SPC

 

[Robin]

That trimming tool is pretty cool Jamie, looks like it would be fast too. I still doing it the old way, but I like it, kind of relaxing.

Robin

 

[Mosinitis]

Different cases can grow at a different rate from the same lot. I trim the whole lot after every firing. For me it's simpler then measuring every case, it also removes the dings on case mouth and keeps cases more consistent.

 

[kev74]

Different cases can grow at a different rate from the same lot. I trim the whole lot after every firing. For me it's simpler then measuring every case, it also removes the dings on case mouth and keeps cases more consistent.

I've bought cars for less than that thing costs.

 

[Mosinitis]

I've bought cars for less than that thing costs.

I bought it when they just came out, about 16 years ago. Price was around $300. It does three operation simultaneously, trimming, deburring and chamfering. Carbide cutter has three sides, each side lasts about a decade. Saved me countless hours of brass prep. Well worth the cost. The guy who makes them is a shooting colleague.

 

[JamieZ]

That trimming tool is pretty cool Jamie, looks like it would be fast too. I still doing it the old way, but I like it, kind of relaxing.

Robin

It is fast,,,,the only thing that bothered me was the price. I have 3 of them for 3 different calibers. Not a shit load of money but enough for someone that doesnt need to reload often,,,I pretty much only shoot when I hunt,,hardly any range time. When I sit down and reload I do about a 100 to 200 at a time. I have roughly 900-223, 350-204 and like 7 or 800 of 6.8.

Plus I have this other little tool that helps with time, deburring, chamfering and primer pocket reamer
Hornady Lock-N-Load Case Prep Trio - MPN: 050160

 

[Mosinitis]

I estimate I trimmed about 80,000 .223 cases over the years. Before Giraud Trimmer, I had Gracey. It works just as fast, but not as user friendly. Adding carbide cutter to Gracey was a big improvement. You can get carbide cutter for Gracey from Giraud or Bob Jones.

 

[Mosinitis]

BTW, If anyone is having problem seeing iron sights due to normal age progression, Bob Jones is the go to guy. He knows how to adjust your vision script for shooting and can make you inexpensive dedicated shooting glasses. He was also the go to guy for very desirable Russian primers, but that ended with sanctions.

bjonessights.com - Control Panel - File Manager

 

[Robin]

That deburring tool looks interesting. While I do enjoy the trimming part, I have a hand held burring tool and do not enjoy that part. Ah me, so many tools.
Robin

 

[Darth]

I use the old Lee cutter stuck in a power drill.

 

[meketrefe]

hi,

The key here is consistency starting with segregating the cases by brand, year, batch and then trimming to the same length.

So first find out where your cases are and pick up a measure from the shorter ones, lets say 1.672 for example.
I would not pick the shortest one but one that is going to allow me to trim from many of them and perhaps left some others
untouched or just barely trimmed.

There is no point of picking a size larger than your shortest cases because you cannot add material, only remove it, and
you want as many as possible to be precisely the same or as close as your trimming system and process allows you.
So given they are within the specs for the case that is a method.

Another method is that you have a lot of brass and you want to further segregate them by length and have lets say 100
with one OAL for one set of loads and another 100 for another OAL and load.

I have all sort of trimming systems. The most accurate trimmer I have is the Forster trimmer that is very popular
among the Bench Rest score competition crowds. I also have their 3 way cutter system that when combined with the forster
lathe they give you the best possible cut one can get and on top on a fast system that is attached to a motor.
I can crank up 100 cases in a couple of minutes that do not need deburring nor chamfering and they are within
1 thousands of each other in the spreads.

This is not possible with any other mechanized trimmers specially those like the giraud that index the case from
the shoulder.

On top the forster is faster and less tiring on the hand when you start moving. The RCBS motorized 3 way is also
a great design but the problem is that the 3way cutter head doesn't achieve the consistency of the forster.

When I say consistency I am not talking about good enough consistency but the same type of consistency one gets
from the single stage cut Bench Rest type of cutter. So one ends up using this 3 way system even for the most
accurate rounds and competition.

@Darth
The Lee will produce pretty decent cuts for the money specially if done in a mini-lathe or quality press they will
produce brass to factory specs tolerances. So I see nothing wrong with it. the concept is the same it measures
from the base to the mouth. So it is not a bad investment and if one has a mechanized unit for chamfering
and deburring it does the work faster and reasonably well even if it is in 2 steps.

Not everyting lee make is great quality but they do make some pretty good and smart things.

 

[Mosinitis]

Perfection can be overdone as demonstrated above. There is no rational reason for the above considerations. Not to mention we are talking about gas gun ammo that will be fired in generous chambers. Many believe that indexing off the shoulder is preferable for consistent neck length. Interestingly the country's top shooters don't fuss about this stuff. Even less so than me.

BTW, US Army Marksmanship Unit (USAMU) uses Giraud trimmers. They have the resources, time and manpower to use any method they believe will produce better results.
They are the top shooters in the country.

 

[Mosinitis]

Use brass from the same lot, fired the same number of times and trim to a minimum length. That's all the consistency you need.

 

[meketrefe]

They are two different things. One would assume the person is sizing the brass accordingly for that chamber and the brass
is already sized and comes from the same dies.

RCBS, forster, Sinclair are very popular with score competition champions, handloaders as well as many other folks.

Agree for a gas gun the LEE will work just as fine as anything else.

Still of all the trimming systems I have bought over the years the Forster is the one that yields the best cuts. But I didn't mentioned
only for that but because if you couple it to a power unit on a carrier is the easiest and less tiring on top of being the most consistent.
It is not the cheapest but it is also not too bad considering all the flexibility it gives.

 

[Mosinitis]

They are two different things. One would assume the person is sizing the brass accordingly for that chamber and the brass
is already sized and comes from the same dies.

RCBS, forster, Sinclair are very popular with score competition champions, handloaders as well as many other folks.

Agree for a gas gun the LEE will work just as fine as anything else.

Still of all the trimming systems I have bought over the years the Forster is the one that yields the best cuts. But I didn't mentioned
only for that but because if you couple it to a power unit on a carrier is the easiest and less tiring on top of being the most consistent.
It is not the cheapest but it is also not too bad considering all the flexibility it gives.

I used Forster trimmer when I started reloading. It does the job well. Most trimmers will do the job good enough to win matches. It's not a critical factor. No need to fuss too much about it. I disagree with the assessment that motorized Forster will do the job faster and easier. Inserting and removing cases will hold up the process. Giraud works like an electric pencil sharpener, it's very quick.
It was good enough for me to hold a 600yard record on some of the ranges. I know what I am talking about from practical standpoint.

 

[thegatman]

Robin
How many cases can you trim for a flintlock?

 

[Mosinitis]

Blueprinting all nails will not produce a better built deck. No reason to go beyond good enough.

 

[Robin]

Robin
How many cases can you trim for a flintlock?

Well, it depends. During the course of the build, maybe one or two, if there is a lot of carving and engraving, four or more. Now thats Bud, so if I had to make a trip to beers of the world, that may shorten the cases but up the cost.
Thank you fellows. I really enjoy learning from knowledgable folks, especially when it is things I didn't know I didn't know.
Robin