Slight 303 confusion .
- Thread starter budman
- Start date
You said reload. The Lee-Enfield is renowned for headspace problems. Brass fired in a LE with excess headspace will stretch, making it susceptible to a separated case (your rifle pulls maybe half an inch out, leaving the rest stuck inside the chamber) - really frustrating. The problem gets more pronounced each time the casing is used.
There are ways around this, but they all start with using new brass rather than try to save money with used.
There are ways around this, but they all start with using new brass rather than try to save money with used.
The Enfield military rifles do not have a across the board headspace problem, the real problem is we are using American commercial SAAMI "civilian" cases in a military rifle. Meaning we are using thinner light weight cases, on top of this our SAAMI resizing dies are much shorter in length and smaller in diameter than the "British" military chamber.
The closest you can get to military brass on newly made cases are Prvi Partizan .303 cases, they have thicker rims, the base diameter of the case is larger and the base of the case is .010 thicker than any other make of .303 British case presently made.
It is my understanding that the Serbian Prvi Partizan company had a contract to produce military grade ammunition and kept British military standards.
Below is a once fired factory loaded Winchester case that stretched and thinned .009 on the first firing and the Enfield rifle headspace was set at just under .067 and within SAAMI standards.
Bottom line the vast majority of cases we are using are not milspec and not built Ford truck tough.
And built like a Chevy............
OK, what happens is this. The .303 Brit headspaces on the front of the rim. Ideally, the face of the bolt should be tight against the back of the case. If there is excess headspace, there's a gap.
Keep in mind that the back end of a casing is thick and hard (good for strength) and the front is thin and fairly soft (good for sealing). When the round is fired, the pressure builds up v quickly and the case starts to expand (pressure pushes in all directions with the same amount of force). The front end, being thin and soft, expands quickly against the wall of the chamber and essentially grabs hold of it (an oversimplification, but work with it). As the pressure keeps building, the case keeps trying to expand. The only direction it can expand however is rearward, to fill that gap between the bolt face and the back of the case. The front end can't move as it is 'glued' to the walls of the chamber, but the back can, so it slams backwards to where it is topped by the bolt. Like pulling taffy, it can get longer, but it gets thinner. A distinct thin ring forms around the case, right before the web.
In serious cases, this can separate the case right there, but that's unusual. More likely is that the case is seriously weakened, so that it will fail after being reloaded and fired again, or several tries on.
A couple of things to do to prevent this. One is to start with a case with a thicker-than-normal rim. This reduces the space between the case and the bolt face. One good brand for this is Privi Partisan, made I think in Serbia. It is available in Canada if you look for it.
A second way is to put a rubber o-ring or rubber band on the case right in front of the rim the first time you fire it. This holds the cartridge back against the bolt face while giving enough support so that the firing pin can fire the primer. What happens is that the case expands at the front, with little or no separation at the rear. Now, if you just neck-size the cases when reloading, the case has already expanded to be the right size for that particular rifle, even if it has excess headspace.
Two lessons for reloaders (asides from using PP brass). The first is to be careful when reloading used brass. The second is to stick to one rifle for one lot of brass.
Hope that helps.
Keep in mind that the back end of a casing is thick and hard (good for strength) and the front is thin and fairly soft (good for sealing). When the round is fired, the pressure builds up v quickly and the case starts to expand (pressure pushes in all directions with the same amount of force). The front end, being thin and soft, expands quickly against the wall of the chamber and essentially grabs hold of it (an oversimplification, but work with it). As the pressure keeps building, the case keeps trying to expand. The only direction it can expand however is rearward, to fill that gap between the bolt face and the back of the case. The front end can't move as it is 'glued' to the walls of the chamber, but the back can, so it slams backwards to where it is topped by the bolt. Like pulling taffy, it can get longer, but it gets thinner. A distinct thin ring forms around the case, right before the web.
In serious cases, this can separate the case right there, but that's unusual. More likely is that the case is seriously weakened, so that it will fail after being reloaded and fired again, or several tries on.
A couple of things to do to prevent this. One is to start with a case with a thicker-than-normal rim. This reduces the space between the case and the bolt face. One good brand for this is Privi Partisan, made I think in Serbia. It is available in Canada if you look for it.
A second way is to put a rubber o-ring or rubber band on the case right in front of the rim the first time you fire it. This holds the cartridge back against the bolt face while giving enough support so that the firing pin can fire the primer. What happens is that the case expands at the front, with little or no separation at the rear. Now, if you just neck-size the cases when reloading, the case has already expanded to be the right size for that particular rifle, even if it has excess headspace.
Two lessons for reloaders (asides from using PP brass). The first is to be careful when reloading used brass. The second is to stick to one rifle for one lot of brass.
Hope that helps.
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Well, I only have the one rifle, I put an ad in the EE for 303 British brass.
I have had two quick replies,but want to make sure the brass is correct to
my Enfield no4mk1.
So I should state that they should strictly 303 british,not any
other brand?
I have had two quick replies,but want to make sure the brass is correct to
my Enfield no4mk1.
So I should state that they should strictly 303 british,not any
other brand?
boltonscouter
CGN frequent flyer
- Location
- parts unknown
303 British is the caliber/size/shape....... not the "make/brand"........ It could be Privi, Winchester, Remington or military surplus etc ....... different makes but all the same dimensions/caliber.
Many different makes/brands of 303 British.
What you don't want is 303 Savage as this is different dimensions/size!
Again, the calibre is 303 British, it's not a brand. Winchester, Remington, federal, ppu, Hornady, and many others make 303 British brass.
If English is your first language, I suggest you get several reloading manuals and read them through before you start reloading. Lyman 49th, the abc's of reloading, Hornady, etc.
To expand on what was said above.
Head clearance or the "air space" between the bolt face and the rear of the case is what causes the case to stretch in the base web area. This is made worse by using thin American SAAMI cases designed for smaller chambers.
The easest way to fire form cases is to place a small thin rubber o-ring around the case as pictured below. BUT this can cause hard bolt closing and gauld the locking lugs if too much force is required to close the bolt, so be careful and grease the locking lugs and use the smallest o-ring possible. Also when the o-ring is compressed it will center the rear of the case at the base of the chamber and aid accuracy after forming to the chamber.
Once the case is fire formed to the chamber the case then can headspace on the shoulder and not the rim to prevent case stretching.
When the fired cases become a snug fit in the chamber you can use a .303 case forming and trim die as a shoulder bump die to push the shoulder back for easy chambering.
Head clearance or the "air space" between the bolt face and the rear of the case is what causes the case to stretch in the base web area. This is made worse by using thin American SAAMI cases designed for smaller chambers.
The easest way to fire form cases is to place a small thin rubber o-ring around the case as pictured below. BUT this can cause hard bolt closing and gauld the locking lugs if too much force is required to close the bolt, so be careful and grease the locking lugs and use the smallest o-ring possible. Also when the o-ring is compressed it will center the rear of the case at the base of the chamber and aid accuracy after forming to the chamber.
Once the case is fire formed to the chamber the case then can headspace on the shoulder and not the rim to prevent case stretching.
When the fired cases become a snug fit in the chamber you can use a .303 case forming and trim die as a shoulder bump die to push the shoulder back for easy chambering.
To be frank, at the risk of quashing somebody's good fortune, .303 British is one round I would never buy used brass for from anyone. It's not unsafe or anything, but the potential PITA factor is just too high. (I carry a split case remover in a pouch fastened to the strap of my Lee-Enfield. Ask me why...)
I would suggest a) getting your headspace checked by a gunsmith (cheap and quick), b) if there is excess headspace (and certainly not all do) finding some PP ammo and c) firing it (with o-ring) before d) reusing the brass (using a collet die for neck-sizing only). Alternatively, buy new brass and even then I would still get the rifle checked and neck-size only.
It is, BTW, possible for a good gunsmith to repair excess headspace.
I would suggest a) getting your headspace checked by a gunsmith (cheap and quick), b) if there is excess headspace (and certainly not all do) finding some PP ammo and c) firing it (with o-ring) before d) reusing the brass (using a collet die for neck-sizing only). Alternatively, buy new brass and even then I would still get the rifle checked and neck-size only.
It is, BTW, possible for a good gunsmith to repair excess headspace.
A member in this thread has offered to help as well and
get together shoot, you are more than welcome join us.
get together shoot, you are more than welcome join us.
boltonscouter
CGN frequent flyer
- Location
- parts unknown
This!!!
Lot's of truth here! Especially if you reload the cases a 4th or 5th time! Will also depend on how hot you load them as to overall case life.
