Shooters Forum banner

1 - 17 of 17 Posts

·
Registered
Joined
·
252 Posts
Discussion Starter · #1 ·
Not sure if this is the right place to ask,but will give it a shot anyway.....

What will it take to form 243 brass in 7mm-08 brass.....And what is
involved in fire forming this brass...Is there a certain bullet-powder
combination to use? Thanks for any advice you can share with me...
I have lots of 243 brass but no 7mm-08 brass....John
 

·
Registered
Joined
·
13,246 Posts
Not sure if this is the right place to ask,but will give it a shot anyway.....

What will it take to form 243 brass in 7mm-08 brass.....And what is
involved in fire forming this brass...Is there a certain bullet-powder
combination to use? Thanks for any advice you can share with me...
I have lots of 243 brass but no 7mm-08 brass....John
John,

You would need a tapered expander die to work the neck up from .243 to .284 and then you would need to check the overall length and possibly trim back to 2.035", because .243 brass is usually about 10 thousandths longer than that. My question is: Why would you go to all that trouble when you can easily buy 7mm-08 brass? It's readily available from Midway or Midsouth Shooters Supply. Even if you have no use for the .243 brass, you could sell it (avoid the cost of the tapered expander die/pin) and buy the new 7mm-08 cases. You'd come out way ahead on the deal and save yourself the work of reforming the cases!
 

·
Registered
Joined
·
1,551 Posts
308 Winchester necked down to 7mm is a 7mm08, a 7mm 08 necked down to 243 is a a 243 W.

Necking a case down lengthens the neck, necking the case up shortens it. the brass in the neck does not get thicker nor thinner, the case body of all three the 243 7mm08 and 308 Winchester is the same therefore the case is formed, firing the case in a chamber does not fire form the case unless the shooter wants to feel as though they accomplished more than they actually accomplished. blowing a case out to remove the tapper at the same time the shoulder is moved forward .125 thousands is fire forming, beyond that cases are formed first when sized and then fired, then the fired case becomes once fired (or fired once)

F. Guffey
 

·
Registered
Joined
·
1,626 Posts
Spring For The Brass

There is plenty of 7-08 brass available.

Buy it.

Nuff said -----pruhdlr
 

·
Registered
Joined
·
1,551 Posts
http://www.nextag.com/7mm_-_08-brass/search-html?nxtg=22840a28050d-B27736424DBF05B5

R-P without shipping and tax $49.00 dollars for 100 cases, then there must be used cases available, again fire forming is not required, forget reduced loads, load the 7mm08, the case is formed when sized.

You have an abundance of 243? lube the case and size in the 7mm08 die, lube the inside of the neck, avoid lubing the shoulder and neck, raise the ram. By the time you have necked up 10 of the cases you will have decided if this is for you.

I purchased an 8mm57 without cases, I purchased a case forming die for $20.00 dollars and 1,400 30/06 cases for .01 cent each, I formed 200 cases for the 8mm57 and did the same for the 7mm57, 7.65X53 B.M. 257 Roberts, 308 Winchester, 35 Whelen 7.7 Japanese and 338/280, point being, the cost of a case is not an issue, I form cases first then fire, I have a 30 Gibbs that requires fire forming,

Remember necking up shortens, trimming may not be required, measure before amd after.

F. Guffey
 

·
Registered
Joined
·
252 Posts
Discussion Starter · #7 ·
Well,it was just a question to ask..I know what you mean about jut buying the brass
and I guess this is what I will do anyway...So thanks for you valuable in put...John
 

·
Registered
Joined
·
788 Posts
Not sure if this is the right place to ask,but will give it a shot anyway.....

What will it take to form 243 brass in 7mm-08 brass.....And what is
involved in fire forming this brass...Is there a certain bullet-powder
combination to use? Thanks for any advice you can share with me...
I have lots of 243 brass but no 7mm-08 brass....John
Pretty harsh.

You can create 7mm-08 cases from .243 in two ways; using your full length sizer to neck up the cases (depending on your die set, the expander ball might be tapered enough to allow you to do this), or to fireform the neck up. If you are using your die, I would recommend putting some lube inside the case neck.

You can fireform the case mouth by using a bullet or by some sort of filler material with a charge of fast burning powder. I have fireformed .358 Winchester cases on occasion using .308 ammunition, but it is a waste of some good bullets and powder, but it works. I have never used a filler to expand necks.

I have always found that necking up will result in thinner brass. As for trimming to length, I wouldn't worry about that as a first matter of course. After you have sized up the neck, load your cases with your planned load development loads and go ahead. There is no need to fireform at this point, as the case bodies and shoulders are essentially the same for .243 and 7mm-08.
 

·
Registered
Joined
·
670 Posts
Do it because you can... It's not too hard and it's time consuming. I reformed some .243 to .308 just for the fun of it.. I had to run it through a 7mm-08 die and the .308 die, move the shoulder a bit and trim, but I didn't have anything better to do at the time..
 

·
Registered
Joined
·
3,749 Posts
Not sure if this is the right place to ask,but will give it a shot anyway.....

What will it take to form 243 brass in 7mm-08 brass.....And what is
involved in fire forming this brass...Is there a certain bullet-powder
combination to use? Thanks for any advice you can share with me...
I have lots of 243 brass but no 7mm-08 brass....John
It's easy to do and only requires a tapered expanding button and lube inside the case neck. I have been shooting the 260 since remington brought it out and I've never bought 260 brass. EVERY round fired in my model 7 in 10+ years is a 243 case necked up. I also neck up 308 cases for my 358 Win, neck up 30-06 cases for my whelen.

Knowing how to neck up or neck down a case is an important skill to know in these troubling and expensive times we live in. 243 cases are a dime a dozen around here so I get them cheap and I never have to worry about finding 260 cases.
 

·
Registered
Joined
·
1,551 Posts
tapered expander? If the dies are RCBS the expander is tapered on newer dies, tapered expanders are available for older dies, the diameter of the assembly determines old or new design. old is smaller in diameter.

F. Guffey
 

·
Registered
Joined
·
32 Posts
It's easy to do and only requires a tapered expanding button and lube inside the case neck. I have been shooting the 260 since remington brought it out and I've never bought 260 brass. EVERY round fired in my model 7 in 10+ years is a 243 case necked up. I also neck up 308 cases for my 358 Win, neck up 30-06 cases for my whelen.

Knowing how to neck up or neck down a case is an important skill to know in these troubling and expensive times we live in. 243 cases are a dime a dozen around here so I get them cheap and I never have to worry about finding 260 cases.

If you don't mind me asking what is wrong with the expander that comes in your .260 rem die? That is what i have been using to convert .243 to .260 brass and haven't encountered any problems yet. Should i be using a different expander in my full length resize die?
 

·
Registered
Joined
·
11,935 Posts
If you don't mind me asking what is wrong with the expander that comes in your .260 rem die? That is what i have been using to convert .243 to .260 brass and haven't encountered any problems yet. Should i be using a different expander in my full length resize die?
Not all sizing dies come with elliptical expanders. If your .260 die set does you are good to go!
 

·
Registered
Joined
·
2,255 Posts
It's really no biggie, I re-appropriate brass on a fairly often basis.

What's slightly more cumbersome is when necking down from a significantly larger caliber, well, for instance .308 to .243. This too can be done, but considering the big step down necks will be thicker, thus requiring some turning in order to provide enough chamber relief, but it's still very doable, not to mention good experience.

SMOA
 
1 - 17 of 17 Posts
Top