Oversized no4 enfield

[Kegcaissy]

Hi all!

Just scored an early production Long Branch 1942 no4 enfield, made in the second month of production for the no4mk1* in that particular factory!! Really cool 2 grooved sporter with early parts that i want to put back to original condition. Still some issues to get rid of before doing a full job on this one: after two slugging attempts, i still get a reading at 0.314'' and even 0.315'', almost in mosin nagant territory with this large bore... I can make some NOE 316299 to 0.315'' but larger than that i'm looking to size down some ideal 323366 and get a 0.316''-0.317'' sizer. What is the largest bullets that can fit in a reliable manner in an enfield no4? I don't care to keep brass and cast for this rifle only but i don't know what is the real limit on boolits size in these enfields...

[leebuilder]

Them 2 groove barrels can go as high as .318. I launch .314 out of my savage no4 mk1* with no problems, try some at .314 with a good alloy and you should be fine I haven't tried any bigger.
Be well

[Der Gebirgsjager]

Like Leebuilder says, if it slugs .314 then try some .314s. If you look around you might find a mold designed for the old German 1888 Commission Rife that started out as a .318 and might be able to shoot them "as cast". I'd give you a number, but it's not worth slogging out to the shop through the snow!

[Jack Stanley]

I've run .318" through my rifles without problem and had excellent accuracy

Jack

[Kegcaissy]

I've run .318" trough my rifles without problem and had excellent accuracy

Jack

Hi!

This is exactly the kind of things i want to hear.

[Sawfish]

Thanks for the info.

[303Guy]

Kegcaissy, you didn't mention what the bore diameter is. That's all that matters - the grooves are just there to spin the boolit and maybe let out some excess gas. But seriously, the boolit needs to fit the throat. That's it - and an unsized neck. I've found that a fired case will seat a boolit of 8.10 ~ 8.20 mm (0.319 ~ .322) firmly. So I make my boolits with that base shank diameter and size and shape the nose section to engage the leade and chamber without the boolit base protruding beyond the shoulder.

I don't care what the groove or bore diameter is. The boolit will get sized down. The problem you need to concern yourself with is what the boolit trailing edge will look like when it leaves the bore. Trailing edge feathering may not be conducive to accuracy - unless it's even all round. That's where I introduced the rebated and chamfered boolit base. With a gas check you would likely not have an issue.

The problem with two-grooves is rifling shearing. Most of my 303's have rust damaged bores but one of my two-grooves has a mint bore. I haven't tried plain cast in it (heck, I've never taken it to the range) but others have had good results in theirs.

My three 2-grooves have groove diameters of around .318 and bores around .304 ~ .305.

[Ballistics in Scotland]

Hi all!

Just scored an early production Long Branch 1942 no4 enfield, made in the second month of production for the no4mk1* in that particular factory!! Really cool 2 grooved sporter with early parts that i want to put back to original condition. Still some issues to get rid of before doing a full job on this one: after two slugging attempts, i still get a reading at 0.314'' and even 0.315'', almost in mosin nagant territory with this large bore... I can make some NOE 316299 to 0.315'' but larger than that i'm looking to size down some ideal 323366 and get a 0.316''-0.317'' sizer. What is the largest bullets that can fit in a reliable manner in an enfield no4? I don't care to keep brass and cast for this rifle only but i don't know what is the real limit on boolits size in these enfields...

This is quite a common thing with the No4, and it reverses the usual wartime order of things by being commoner in the early production. I believe it is because they used single-pass broaching tools to rifle the barrels - a technique unlikely to equal modern after-market barrels for accuracy, but not at all bad when it is done right. The trouble is... just look at the price of spline broaching tools online, and imagine making them helical. I believe they started with those expensive tools oversized to make them last for the maximum number of resharpenings. Logic suggests that they ended up making perfectly dimensioned or tight ones too, and one of these decades I will probably meet someone who has one.

The good news is that neither did I ever meet anyone with a rifle with a chamber neck too tight to accept rounds loaded with groove-diameter bullets. It needs to be checked for, though. I believe .303guy is right, at least as far as safety is concerned, for squeezing even .318 bullets through "official"-diameter grooves. (The only exception I can think of would be if someone makes solid brass or copper ones, steel-cored military ball being unlikely to have existed.) But a very tight bullet and a case-neck prevented from expanding away from it by the chamber, are two bearable evils which may not be as they add up.

I believe various firms even make jacketed bullets for the J-bore, pre-98 8x57. I would have no qualms about sizing them down a little, if the groove diameter is less, for I think it may matter as far as accuracy is concerned. Excess bullet diameter is, as has been said, liable to lead to finning at the rear. For cast ones, both a gas-check and groove-diameter sizing would be advisable to limit this.

People will tell you that sizing down a jacketed bullet can cause eccentricity of mass, because jacket metal springs a little larger on emerging from the die, and the lead core doesn't. But I doubt that when the sizing is only a few thousandths, a conventional long ogive isn't sized at all, and the rear of a jacketed bullet is usually slightly radiused.

[303Guy]

I should emphasize that I was referring to cast lead alloy bullets or paper patched bullets. I read somewhere that the deep groove on the 2-groove was to accommodate displaced bullet material, considering that the grooves are quite narrow. That does make sense so maybe?

One of my 2-grooves shoots PRVI 180gr semi-spitzer, semi-boattail bullets with a .310 diameter, just fine. Very fine actually. I think it's more to do with the ogive and how close to the leade it sits. With this bullet the jump is quite short. I have a recovered jacket that shows how well the bullet fits in and is supported by the bore.

Here is what can happen if the boolit doesn't seal the groove.


And this one sealed. It was patched.


Here you can see partial rifling shear. I don't see that it would affect accuracy.