7-08 Brass....& its Length

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7-08 Brass....& its Length

Post by Stix » 18 Sep 2018, 8:41 pm

Sorry to ask it again...but i thought id ask in its own thread.

So, 7-08 brass...anyone know of any issue with the brass being 100 thou (.010") under trim to (minimum suggested) length...?

What do other 7-08 re-loaders do...?

Anyone use .308 brass in theirs...?

Cheers
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Re: 7-08 Brass....& its Length

Post by bladeracer » 18 Sep 2018, 8:55 pm

Stix wrote:Sorry to ask it again...but i thought id ask in its own thread.

So, 7-08 brass...anyone know of any issue with the brass being 100 thou (.010") under trim to (minimum suggested) length...?

What do other 7-08 re-loaders do...?

Anyone use .308 brass in theirs...?

Cheers


100-thou is a tenth of an inch or 0.100" or 2.5mm.
It wouldn't worry me as long as it holds the bullet securely.
Consistent length is good though.
All my brass is stamped 7mm-08.
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Re: 7-08 Brass....& its Length

Post by Stix » 18 Sep 2018, 9:18 pm

Thanks blade.

And sorry for the lesdixia... :oops:

I mean, .010" under...in other words, trim length is 2.025", but these are 2.015"...
(growing them will take ages as i mostly neck size)
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Re: 7-08 Brass....& its Length

Post by bladeracer » 18 Sep 2018, 10:03 pm

Stix wrote:Thanks blade.

And sorry for the lesdixia... :oops:

I mean, .010" under...in other words, trim length is 2.025", but these are 2.015"...
(growing them will take ages as i mostly neck size)


10-thou is nothing but if you're concerned I would trim everything to the shortest and just forget about having to trim them again for a while.
I doubt you'd see a measurable difference in group size or velocity due to the variation.
I guess it's remotely possible that constantly shooting short brass might cause some erosion of the front part of the chamber, but the alternative is throwing out all your short brass.
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Re: 7-08 Brass....& its Length

Post by Cooper » 19 Sep 2018, 9:37 am

I just use Norma 7mm 08 brass. I do have some 308 brass. But never got around to trying it. I guess the neck might end up slightly thicker which might cause higher pressures. I kind of like using the correct head stamp in each rifle. Just for my own piece of mind. I wouldn't be worried about the lenght being slightly under minimum length.
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Re: 7-08 Brass....& its Length

Post by Gamerancher » 19 Sep 2018, 10:35 am

Sizing brass down results in thickening of the neck, the extra brass has to go somewhere. Thick necks can cause problems with neck tension and subsequent pressure spikes in a tight chamber. Either buy correct brass, neck 243 up, or get into neck turning.( yuck )

.010" in case length is 5/8ths of f-all in the grand scheme of things, I highly doubt you will be able to detect any difference.
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Re: 7-08 Brass....& its Length

Post by Stix » 19 Sep 2018, 1:52 pm

Thanks guys...

I had read some horror stories in regard to shorter brass....even if its only 5/8ths of f-all...

Gamerancher, the brass im using (in this instance) is win & its cheap, & its primarily for hunting so i dont waste an hour crying while looking for the ejected case(s) i cant find...

This brass appears to be thin enough to have the required neck clearance without (pressure) issues.
Measuring these fresh FL sized cases indicates a clear .004" (.005" in most cases) total (OD) neck clearance for the loaded round.
(There certainly doesn't appear any 'obvious' pressure signs upon firing)

I assume .002" clearance all around is enough...? :unknown:

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Re: 7-08 Brass....& its Length

Post by bigrich » 19 Sep 2018, 6:43 pm

Stix wrote:Sorry to ask it again...but i thought id ask in its own thread.

So, 7-08 brass...anyone know of any issue with the brass being 100 thou (.010") under trim to (minimum suggested) length...?

What do other 7-08 re-loaders do...?

Anyone use .308 brass in theirs...?

Cheers


100 thou stix ? i thought it was unusual for factory federal 222 ammo to be 25 thou under trim length. doesn't seem to affect accuracy but :unknown: :thumbsup:
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Re: 7-08 Brass....& its Length

Post by bigrich » 19 Sep 2018, 6:46 pm

i shoulda read the rest of the post :lol: my previous post is accurate though. using digital verniers , factory federal 222 ammo i have is 25 thou under trim length. works fine and reloads fine so 10 thou should be cool bud :thumbsup:
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Re: 7-08 Brass....& its Length

Post by Chronos » 19 Sep 2018, 8:28 pm

I’ve been using Lapua .308W brass in my 7-08 for about 6 years. The same 300 cases have been reloaded a minimum of 10 times for a total of about 4000 rounds.

When I sold my .308W I necked down all the brass, trimmed to the shorted length (much much shorter than .010” under length)

I heard all the horror stories about neck thickness and donuts.....

In all these years I’ve never neck turned or reamed necks and never checked length and never trimmed. Cases shoot sub 1/2moa with boring monotony and have shot dozens of groups in the .3’s

I assume one day something will read it’s head and I’ll run into issues......

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Re: 7-08 Brass....& its Length

Post by SCJ429 » 20 Sep 2018, 12:19 pm

What is the problem with neck turning Gameranger? I neck turn most of my brass. I do it as part of case prep and it doesn't take too long. You do need the right tool but it isn't very expensive.
I don't think you would run into problems with running out of room for the neck to expand enough to release the projectile with factory generous chambering but run your calibers over a fired case to see how much space you need to be safe.
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Re: 7-08 Brass....& its Length

Post by marksman » 20 Sep 2018, 9:14 pm

Chronos wrote:I’ve been using Lapua .308W brass in my 7-08 for about 6 years. The same 300 cases have been reloaded a minimum of 10 times for a total of about 4000 rounds.

When I sold my .308W I necked down all the brass, trimmed to the shorted length (much much shorter than .010” under length)

I heard all the horror stories about neck thickness and donuts.....

In all these years I’ve never neck turned or reamed necks and never checked length and never trimmed. Cases shoot sub 1/2moa with boring monotony and have shot dozens of groups in the .3’s

I assume one day something will read it’s head and I’ll run into issues......

Chronos


to not have any issues Chronos you must have found the right mild load that just shoots in your rifle and doesn't effect your cases :drinks:
not trying to scare you or anything :D :thumbsup:

if your brass is a bit short Stix IMO I wouldn't worry to much about it but would make sure I clean the neck throat area thoroughly every couple of hundred rounds, you can get a buildup in this area of carbon that sets like ceramic and is very hard to get out, I have trouble with my 22-250 with this and use carby/throttle body cleaner to get it out occasionally, you can feel this when pushing a patch through, hard to start then slips nicely after an inch or so
:drinks: :thumbsup:
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