Fire forming 303 brit

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Dead eye Joe

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Hi all
I have a large quantity of 150gr 303 bullets that I got cheap and would like to use to fire form brass for my SMLE.

The cases stretch way less with light loads than with full power loads.
Is there a powder that you would suggest?
And how much (how little) powder would be safe to shoot really low powered loads?
Thanks
Joe
 
Don't over think it. Use a published starting load for that caliber and bullet. Remember, going under the starting load can result in over-pressure too...

Dead eye Joe said:
Hi all
I have a large quantity of 150gr 303 bullets that I got cheap and would like to use to fire form brass for my SMLE.

The cases stretch way less with light loads than with full power loads.
Is there a powder that you would suggest?
And how much (how little) powder would be safe to shoot really low powered loads?
Thanks
Joe
Click to expand...
 
If you want low power and crazy long case life, use Trail Boss.

I load 14.5 grains of TB and top it with a 185 grain Lee cast bullet and it's snappy enough to shoot out to about 100 yards, but the recoil is very mild and there's not much noise. I'm sure this load has enough juice to form brass.
 
Dead eye Joe said:
Where do you guys get o-rings from?
I am having a hell of a time getting them locally
Click to expand...

I get them from a local fastener store. I've seen them individually in the fastener section at Home Depot, Rona, Lowes, and the like.

This is a long but very informative thread about reloading for .303 British:
http://www.milsurps.com/showthread.php?t=24699

There are some pics and even animated .gif's in there that explain the issues and how to prevent them. One guy says he averaged 5 firings with new brass when full length resizing and managed to reach 32 firings using the o-ring method and only neck sizing.

The issue isn't with .303 British cases in general but specifically US .303 British cases which actually aren't to SAAMI dimensions. PRVI Partisan brass is supposedly the closest to original British Army dimensions and doesn't require the o-ring trick necessarily.
 
I went to several Rona/Home Depots and plumber shops and no one had a good selection.
I was able to find some that were just a tad to thick.

Have not found any since.
How many firings do you get on average per o-ring?
 
You only need the o-ring for fire forming the cases initially. After that if you only neck size it will already be long enough to not move around and will headspace off the shoulder instead of the rim. After a few firings you may need to full length resize if the shoulder creeps forward (never happened to me but many have had it happen) then you need to do the o-ring trick again to fire form the case.

I am only up to 2 firings because I only started to use the o-ring trick on my last couple trips to the range. There is no stretching near the head visible on the outside of the case like there is when I don't use an o-ring so I suppose it's working. So far my o-rings (I put one on each shell when I reload them instead of using one and swapping it after each shot) have lasted that long. One of the guys in the thread I linked to said he fire formed 100 cases with the same o-ring and it wasn't visible worn yet.
 
" After a few firings you may need to full length resize if the shoulder creeps forward----"

Instead of neck sizing, and later having to full length rezise, set the dies from the start to just barely kiss the shoulder of the case. Carefully set them exactly right the first time, then lock them solid, as you will never have to change them again.
Set the dies so they just touch the shoulder. That won't push the shoulder back and shorten the case, but it will not let the case grow and the brass should last for a great many loadings.
 
H4831 said:
" After a few firings you may need to full length resize if the shoulder creeps forward----"

Instead of neck sizing, and later having to full length rezise, set the dies from the start to just barely kiss the shoulder of the case. Carefully set them exactly right the first time, then lock them solid, as you will never have to change them again.
Set the dies so they just touch the shoulder. That won't push the shoulder back and shorten the case, but it will not let the case grow and the brass should last for a great many loadings.
Click to expand...

I have done this and it works great. One thing I'd like to add, dental floss works fine if you can't find rubber rings. I try to use the mint flavoured kind because it leaves a nice fragrance in the action.
 
Where to get orings?

Theres a oring suppy store in toronto, which will have any size you can imagine. Its called able o-rings. I dont know if they ship.

Another place you can get them is from oringmonkey.com They are US based but i dont imagine you will be buying more than $20 worth, so you wont be paying any border fees. If i remember correctly their USPS shipping rates to canada were very reasonable.

Depending on headspace you will need sizes 008 009 or 010. I couldnt close the action with any of these on my PPU ammo. Winchester brass on my no1 fit all of these, but on the no4, 008 only.
I havent tried metric sizes, but they are usually thinner.

Use Buna, not urithane o-rings. The buna nitrile are more resistant to heat. Ive had urithanes melt on me.
 
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I found a few orings at Home Depot, but they were grossly over priced. On Ebay, I found a seller that had packages of 50 for $1.50 and $2.50 ship ! They were excellent. Description is : Buna Orings,#012-90D, 50 pieces, size 3/8 x 1/2 x 1/16, the size we need for fire forming. Some servived the first firing so I was able to get two uses from them. A super buy, it's well worth it !!
 
H4831 said:
" After a few firings you may need to full length resize if the shoulder creeps forward----"

Instead of neck sizing, and later having to full length rezise, set the dies from the start to just barely kiss the shoulder of the case. Carefully set them exactly right the first time, then lock them solid, as you will never have to change them again.
Set the dies so they just touch the shoulder. That won't push the shoulder back and shorten the case, but it will not let the case grow and the brass should last for a great many loadings.
Click to expand...

id just neck size much easier for the new reloaders what your talking about is a little more advanced

i like the lee classic loader


i use the oring on all brass right now im using prvi and mk7 ball that was fired years ago in this gun i neck size only and anneal every few firings ive gotten close to that 30 firings out of my brass but i am using cast reloads witch are not that hard on the brass to begin with
 
Can't find o-rings in Calgary??? Go to a farm or auto supply joint such as Co-op, NAPA etc. They will have o-rings enough to fill the trunk of your car! :)
 
I just ordered 50 each of 008,009,010 from oringmonkey.com as dannyd123 suggested.
23 bucks incl shipping.
Compared to the 50c per I paid for some locally that did not fit anyway it's a bargain.

thanks all
 
Dead eye Joe said:
I just ordered 50 each of 008,009,010 from oringmonkey.com as dannyd123 suggested.
23 bucks incl shipping.
Compared to the 50c per I paid for some locally that did not fit anyway it's a bargain.

thanks all
Click to expand...

Glad I could help.

Just looked up metric specs:

The metric equivalent to 010 size is M1.5x6mm. But if you want something that will fit better on the cartriges, M1x8mm will work beautifully. These are smaller in thickness than any of the standard sized o-rings and should fit if the other o-ring sizes dont work.

So if standard sizes 008-010 dont allow you to close the action, try M1x8mm, this is the smallest size you can get that will fit the brass correctly. Ill have to try this on my PPU ammo.
 
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