re-barrel a No.4 Mk.I?


Erik Jensen
October 1, 2008, 02:10 PM
so, a while back, I got an Enfield No.4 Mk.I with my C&R. took it to the range, fired a box of Remington commercial .303. looked at the target. target looked like an aerial photo of the Spanish Armada! this from only 50yds at the Bass Pro Shops range.

maybe my barrel is too big for the commercial ammo. maybe the muzzle is screwed, and it could be counter-bored. but if I need a new barrel, where can I find one? does anyone have any 'smith recommendations? especially in SE Michigan?

I haven't tried this rifle but the one time, and I don't like the idea of a rifle that just sits on the rack and looks pretty.

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October 1, 2008, 04:14 PM
Start by checking the headspace. That's a safety thing not an accuracy thing though. Then, if the headspace is ok, slug the bore. Hammer a cast .30 calibre bullet or a soft lead fishing sinker through the barrel, preferrably from the chamber end, using a bras srod and a plastic mallet. Then measure the bullet/sinker. Lee-Enfield barrels can measure from .311" to .315" and still be considered ok. Larger than .315", the barrel is shot out. If the barrel measures ok, use the closest bullet you can. Most factory ammo uses a .312" bullet. If your barrel measures .314" or .315", accuracy will suffer.
Steve at is selling .313" and .314" 200 grain jacketed bullets too.
If the bore diameter is ok, have a look at the crown. Any nicks, dents, etc.? If so, have it re-crowned. Any smithy can do that. Brownell's sells the tool, but it's kind of pricey for a one time job.
You won't likely be able to find a new barrel. You will find a decent used one though. Gunparts is listing "very good" No. 4 Rifle barrels with the front sight base at $59.95 plus $1 shipping.

Erik Jensen
October 1, 2008, 04:26 PM
I just called a smith I used to deal with. I'll drop it off tomorrow. I've been meaning to get into handloading, and if the bore is just too larger for the ammo I used, this will push me towards actually doing it. I'll see what the 'smith says.

Jeff F
October 1, 2008, 09:02 PM
Erik, it would probably be cheaper to buy another Enfield then it would be trying to re barrel it.

Ian Sean
October 2, 2008, 12:17 AM
I recently picked up a "flea-market special" 1/2 sporterized #4 MK 1 myself for $40. All bubba did was remove the front hand guards and cut the stock off, thank god.

But the chamber looked like the grand canyon....bad erosion. Numrich had some take of barrels and I got a beauty (very crisp rifling) in nice shape. Also picked up the missing parts to make it a "military" gun again.


Still showing they have barrels in stock..going for $60 now.

October 2, 2008, 11:12 AM
There's a thread on the forums about re-bedding the handguards on an enfield. The before and after pictures of targets that were posted were pretty impressive. Might want to give it a shot before diving into a rebarreling project.

Erik Jensen
October 2, 2008, 11:19 AM
well, I'm sure it needs more work than just re-bedding the handguards. I wouldn't think it would be keyholing at 50 yds if it was just a minor problem.

I'm just a little peeved that I paid AIM extra to get the micrometer sights, and then find that it won't even stabilize the bullet. of course, I only tried the Remington ammo. I have some surplus .303 I should mic out and test.

October 2, 2008, 11:55 AM

You do not actually tell us how big your groups were at 50 yards. This would help.

Look over the barrel condition carefully. That sort of inaccuracy is going to have a very obvious cause. Check for barrel corrosion and chamber throat erosion. Original British ammo used corrosive primers so if the rifle was not cleaned properly there could be corrosion in the barrel but this will be very easy to see.

I think it would be worth confirming that the new sights are correctly fitted. It does not take much sight movement to provide a serious aiming error.

Make sure there is a short cylindrical spacer between the trigger guard and the action. This spacer fits around the large screw (at the front) that holds the trigger guard in place.

If you must have a new barrel, and originality is not an issue, you can fit a 308 sporter barrel and chamber it for a 303 cartridge (this should really use a custom reamer with the correct throat, they are available). By using a mixture of 308 and 303 reloading die parts you can produce a 303 case with a 308 bullet in a high-quality barrel. This has several advantages, there is a wider range of bullets available, the 303 headspace problem can be dealt with when the new chamber is cut, accuracy is excellent.

I have done several of these conversions. I call it the 7.62 British to remove confusion with the original 303 British caliber.

October 2, 2008, 12:35 PM
{"I'm just a little peeved that I paid AIM extra to get the micrometer sights, and then find that it won't even stabilize the bullet."}

Got reamed by them recently on a No4 Mk1 myself. Didn't expect a pristine gun for the price but I expected shootable. The barrel on the 303 Enfield I recieved from them was worn completely out and won't keep 3 shots inside 10 inches at 50 yards. I am considering having the barrel replaced on mine as well. Either that or just leaving it as a wallhanger. Lessons learned? Won't deal with them again and will never buy another surplus rifle that I can't inspect myself or that doesn't include a description of the bore condition.

Erik Jensen
October 7, 2008, 11:06 AM
well, I took it to my smith last night. barrel is fine at the muzzle, at least it checks out fine using a surplus round. headspace is pretty bad, though. I can't quite make out what number the bolt face is. the number on it was not struck square, and all I can see is the curved part, so it's either a 2 or a 3. if it's a 2, I might be able to find a #3, and that might fix it. if it's a #3, there's not a whole lot I can do, and it will likely be a wallhanger.

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