Gun Talk: Headspace Problem?

[JohnRich 4]

Shootin' match Sunday, 300 yards. Started out with an Enfield #5 Jungle Carbine, and my reloads were a little too long for that rifle and I had to force the bolt to close and lock on the cartridges. After the first stage, I decided that rifle wasn't performing very well, so I switched to an Enfield #4, using the same ammo. And this time the ammo was so loose in the chamber that about every other shot caused a case head separation, as shown in the attached photos. So I had to give up on that one too.

I had my handy .303 broken shell extractor in my gun tool box, and kept it busy.

So now I've got to resize my .303 cases customized depending upon in which rifle they will be fired. That's a pain in the arse to keep up with...

Or maybe I can change out the bolt heads to make them uniform between rifles. The Brits were a bit clever with the Enfield design, with bolt heads that can be swapped with different ones as a chamber wears out, to keep up with growing headspace and keep it within tolerances.

[dannydan 5]

gots two Ishahpores in .308! one in casmo just waiting on my ass to get in gear.... love them! caliber to stay in line with others and because it's common. Still want that Jungle also just for gp... ;)

[airtwardo 7]

You ARE using .303 not .308 right?


but seriously~


I have a #5 too!

Couple things John, are you resizing full case length at each reloading? That's not necessary if you keep the ammo separate regarding which gun it's used in.

Are you trimming to length each reloading?

.303's are notoriously known for growing, maybe the the rounds fired in the jungle carbine were fired in the #4 long rifle last time, and that has a lot more head-space?

I'd also be curious as to how many times those broken ones had been reloaded...

How deep of a crimp are you putting on them?

If it's too much you may be raising chamber pressure enough to cause that...with a bullet puller, bungee-cord and fish scale you can get an idea if the factory ammo is significantly 'looser' than your reloads.

~ If you choke a Smurf, what color does it turn? ~

[dannydan 5]

yeah those are .303British casings sir AiR T. I'm kinda jealous of you both actually... I picked uP my two back in the day they were under eighty bucks each, and i already had 4 other 7.62 s.

[airtwardo 7]

I didn't mean the casings...I meant the bullets!

I picked up my jungle carbine from a neighbor for 40 bucks back when I was 16...the steel is pristine, he sanded the stock and varnished it...

about 20 years ago I found a bayonet for it...cost me more than the gun!

~ If you choke a Smurf, what color does it turn? ~

[sfzombie 3]

how much is an ishapore worth? i've had one for years, i traded a saddle for it. just wondering...i'd like to trade it maybe, but it is a hell of a gun...

http://kitswv.com

[airtwardo 7]

Quote

how much is an ishapore worth? i've had one for years, i traded a saddle for it. just wondering...i'd like to trade it maybe, but it is a hell of a gun...

http://www.youtube.com/watch?v=41gy62X4QXI&feature=related

Trade ya 6 muskrat & 2 bear pelts ...and a salt block!

~ If you choke a Smurf, what color does it turn? ~

[steve1 5]

That sure sounds like a headspace problem to me. I've only had a separation like that once. I knew something was wrong because all the hot gases came back in my face. Then the bolt was almost frozen shut....My problem was that the load was way too hot....I've never had a separation several times in a row. It might be good to have a gunsmith look at that chamber. Were those brass reloaded very many times?

I know different rifles have different pressures. Do you think this load was too hot in that other rifle?

I had a 25/06 Ackley barrel on a gun. I used to fire form regular 25/06 brass in it. The shoulder was all different. That worked okay. I know you can lengthen the length of your resizing die to possibly fireform your brass. If the headspace is too long... this may lead to further seperations.

I wonder what it would cost to have that chamber rebored to something bigger....if headspace is the problem.

[JohnRich 4]

These cases are full-length re-sized.

I haven't been in the habit of segregating my ammo reloads by gun. I own about 6 Enfields for example, and it gets to be a bit much to have 6 different batches of ammo, one for each gun. I prefer to just have one batch of .303, that will shoot reasonably well in any of the six Enfield rifles. But as it appears now, that may no longer be possible.

I trim cases after every re-size to keep them within spec for length.

.303's do have a reputation for loose chambers and eating up brass much quicker than most guns.

Number of times reloaded? Don't remember. Not more than once or twice. I don't keep up with that, but a I should. Usually, once I start seeing problems, like in this case, I throw out the whole batch and start over again with a new batch.

I don't crimp my necks to the bullet. I don't have one of those neck uniformer tools to keep the neck tension the same on all bullets. I can feel the neck tension when seating the bullets, and if some are noteably tight, I either throw them out or segregate them in the ammo box and mark them, so that I'll know when shooting them that those were "tight necks". I've never noticed any difference in accuracy or behavior from those kind of rounds.

I'll have to use the "soot" technique to figure out exactly how long to resize the cases in those rifles. With that technique, you use a candle to lay down some soot on the neck of a fired and re-sized case, sized intentionally on the long end. Then you insert it into the chamber and close the bolt. If the soot is all smudged, you know the neck is touching in the chamber, and then you can back off a few thousandths to get it exactly where you want it, as seen when the soot is no longer smudged.

I've also used plastigauge for this kind of thing in the past. Plastiguage looks like a spaghetti noodle made out of play-dough clay. It comes in different diameters, and when squished between two things, it flattens out in a predictable way. By measuring the width of the flattened plastiguage, and comparing that to a chart on the product packaging, it tells you what the tolerance is between the two parts. If it's not squished at all, then obviously the tolerance is greater than the diameter of the plastiguage, and you then use a larger diameter version. This is used mostly in the automotive business I believe, and can be purchased at auto parts stores.

All of that is a lot of work for a beat-up old WWII rifle. I go to great lengths for accuracy for my modern long-range rifles, but for the military surplus stuff I like to just pick 'em up with military surplus ammo and go.

I don't think the load is too hot, as it's well within the recommendations for max powder charge. I think it's a reloading problem on my part.

I have "check dies" for most of the calibers I reload, but I don't have one for .303, and I'll order one of those. A check die is like an exact copy of the SAAMI spec chamber in a hand held form. You insert the case in the check die to see if it fits properly, and the die has "steps" on both ends to make sure your case length falls between the allowable tolerances for length, long and short, for both the neck and head.

I don't think the rifle chamber is the problem, because this was one of the Royal Irish Constabulary rifles that were released about 10 years ago or so, and I received it "brand new", dated 1954, still in the original factory wax mummy wrap. It only has a couple hundred rounds through it.

Part of the fun of these old guns is figuring them out and fiddling with them to make them shoot good. This one needs more fiddling.

[skiskyrock 0]

Any chance you may have swapped bolts or bolt heads at some point? That could make one too tight and one too loose.

[winsor 236]

With something like a .303 SMLE, I highly recommend Lee Collet Dies. They very accurately neck resize without touching the shoulder, which greatly reduces the problems associated with full-length resizing.

Since you have a bunch of them (I only have a Ross and a No. 4 Mk. I), it might make sense to get them to some common chamber dimension. You can swap out bolts until they are pretty much in agreement and/or or you can have a talented gunsmith bring them into standard chamber dimensions. The latter approach might make sense for M-1 Garand built to National Match standards (mine is exquisitely accurate), but is likely more than is warranted for military grade Enfields.

Even though the .303 is limited to 45,000 CUP, case failure is a bad thing. It is better to wear protective glasses and not need them and all that.

At any rate, the kind of case failure you depicted rarely occurs the first time the case is subjected to excessive headspace, so I suspect a lot of your reloaded ammo is compromised.

I tend to fire Berdan primed surplus ammo when I can, so what happens after reloading is not much of an issue. Perhaps you could headspace your .303s and only use those within SAAMI specs for Boxer primed ammo you intend to reload. The rest can be relegated to disposable-brass ammo.


BSBD,

Winsor

[dannydan 5]

Quote

With something like a .303 SMLE, I highly recommend Lee Collet Dies. They very accurately neck resize without touching the shoulder, which greatly reduces the problems associated with full-length resizing.

Since you have a bunch of them (I only have a Ross and a No. 4 Mk. I), it might make sense to get them to some common chamber dimension. You can swap out bolts until they are pretty much in agreement and/or or you can have a talented gunsmith bring them into standard chamber dimensions. The latter approach might make sense for M-1 Garand built to National Match standards (mine is exquisitely accurate), but is likely more than is warranted for military grade Enfields.

Even though the .303 is limited to 45,000 CUP, case failure is a bad thing. It is better to wear protective glasses and not need them and all that.

At any rate, the kind of case failure you depicted rarely occurs the first time the case is subjected to excessive headspace, so I suspect a lot of your reloaded ammo is compromised.

I tend to fire Berdan primed surplus ammo when I can, so what happens after reloading is not much of an issue. Perhaps you could headspace your .303s and only use those within SAAMI specs for Boxer primed ammo you intend to reload. The rest can be relegated to disposable-brass ammo.


BSBD,

Winsor

WHERE IS THE FREKIN "LIKE" BUTTON! :)

[fernjack455 0]

Quote

You ARE using .303 not .308 right?


but seriously~


I have a #5 too!

Couple things John, are you resizing full case length at each reloading? That's not necessary if you keep the ammo separate regarding which gun it's used in.

Are you trimming to length each reloading?

.303's are notoriously known for growing, maybe the the rounds fired in the jungle carbine were fired in the #4 long rifle last time, and that has a lot more head-space?

I'd also be curious as to how many times those broken ones had been reloaded...

How deep of a crimp are you putting on them?

If it's too much you may be raising chamber pressure enough to cause that...with a bullet puller, bungee-cord and fish scale you can get an idea if the factory ammo is significantly 'looser' than your reloads.

+1 on all.
It appears to be either excessive head space or as already posted the bolt head may need to be checked. I have 5 Enfields and have checked all with erosion gauges. 2- #4, 1- #3, 1- 2A, 7.62, 1-#5,

[loch1957 0]

John the chambers were intentionally made sloppy to aid in the battle field,so the brass tends to distort a bit. The locking lugs or their abutments in the receiver can get beaten back, causing excess head space. They don't have locking lugs like a modern bolt action, they do not like hot loaded ammo and its not safe, if they are reloads back off powder. If its surplus ammo try to find a bolt, or swap one from different rifle to see if results are the same.

And for the record, 7.62x51mm and 308 are not the same cartridge, quit interchanging them.

But on cool trivia side, the British discovered cool fact about the rifle ammo. The 303 if you pull the slug and set it backwards, its armor piercing. Soldiers would keep a handful of rounds like that as they would penetrate light armor.

Avoiding danger is no safer in the long run than outright exposure. Life is either a daring adventure, or nothing.”

[steve1 5]

I used to leave space between my resizing die and the plunger. I heard the case would fit the chamber better that way, as long as you used the brass in the same rifle. It was supposed to help accuracy, somewhat. After a couple firings it got really hard to close the bolt. I now full length resize all my cases. I just got tired of having to force the bolt closed...I didn't notice any great improvement in accuracy, but some people swear by neck sizing only.

[JohnRich 4]

Quote

I used to leave space between my resizing die and the plunger. I heard the case would fit the chamber better that way, as long as you used the brass in the same rifle. It was supposed to help accuracy, somewhat. After a couple firings it got really hard to close the bolt. I now full length resize all my cases. I just got tired of having to force the bolt closed...I didn't notice any great improvement in accuracy, but some people swear by neck sizing only.

If you're having to force it closed, then that's an indication that something isn't quite right, IMO. I don't like that. The idea with neck-sizing is that in a bolt rifle you can use your bolt's leverage to force a tight cartridge closed, and that a cartridge which fits the chamber perfectly with no loose space is more accurate than a loose fit. There is something to be said for that. So then the idea is to only resize the neck as necessary to fit a new bullet. Neck sizing is not recommended for semi-auto rifles because you need a loose fit to make the semi-auto function work properly, so for those you use full-length sizing. A tight fit on a semi-auto can give you malfunctions, failure to feed or failure to extract.

That press technique sounds like just making the case longer, perhaps with the goal of getting the bullet closer to the rifling. Having the bullet actually jammed into the rifling can be dangerous, as that increases pressure as there is resistance to the bullet moving when the powder ignites. So usually you set the bullet back a bit so it has to jump a small gap once expelled from the case and before it burrows into the rifling. That allows a little pressure release as things get started. Generally, the smaller that gap, the more accurate, but you do want to have some gap.

The way to play with that with with reloading is to seat a bullet long, cover the bullet with soot from a candle, and then chamber it and close the bolt. Remove it, and if it's touching the rifling you'll see the impressions in the soot. Then you seat the bullet a little deeper, say a hundredth of an inch, and repeat the process. You keep doing that until the soot is no longer disturbed, indicating that you are now off the rifling. Then make up batches of 5 cartridges each at various bullet seating depths, and label them. Go out and shoot 5-shot groups with each batch. One batch will likely be noticably better than the others - that's the sweet spot. Then record that as the way to load all your future reloads for that gun. There are also fancy-schmancy scientific tools to do this, but they cost money, and candles are cheap.

[steve1 5]

Having the bullet almost touch the rifling makes a huge difference in accuracy, in my opinion. I've tried most of the reloading tricks to improve accuracy. This is one to remember....

This is hard to do with all guns though. My one and only Winchester model 70 has a fairly short throat. The bullets fit fine in that magazine.

My Remington 700's have a really long throat. That means not having enough bullet left in the case neck, when I use 130 grain bullets in 270. Sometimes the bullet will come out and even stick in the chamber of your rifle, if you don't crimp the bullet.

I think I told that story earlier. I had made a successful stalk on a buck antelope. I openned the bolt to make sure the bullet was still chambered. Luckily I pointed the gun up when I did that. There was the cartridge case...but no bullet on the end. Luckily all the powder didn't spill all over. The bullet was stuck in the chamber. I closed the bolt to reseat that bullet. Then I shot the antelope.

After that I made sure that I put a crimp on those bullets. That eliminated the loose fit on those bullets.

Another problem that we talked about earlier, John is that some rifles have too short of a magazine to load your bullets out there, (long enough to almost touch the rifling).

I just bought a Savage 99 rifle. There is no way I can load the bullets long, unless I feed them one at a time into the chamber.

Another time I reloaded a box of ammo too long. There was no way I could close the bolt on those rounds. This could have ruined my hunt that day. Luckily I found some other rounds that would fit.

For hunting rounds I'll load them a little deeper. I figure if I have a dirty round or something, I want it to still chamber okay.

Loading the bullets to where they almost touch the rifling, is one reloading trick that really makes a difference. I usually use a magic marker to blacken the bullet, and then watch for signs of the bullet touching the rifling....

I know what many are thinking....how accurate do you really need a rifle. Many shoot a rifle that groups three or four inches at 100 yards. Most of my rifles will shoot close to 3/4 of an inch at that range. At four or five hundred yards this adds up to a big difference. I rarely shoot at that range, because I don't want to wound something, but If I have to, I can usually make that kind of shot. It all adds up to confidence in your shooting ability and rifle.