303 Brit

Not open for further replies.


Dec 6, 2010
I inherited some 303 Brit brass and bullets from my Uncle Joe when he passed away back in 2001. (Not sure where the rifle went, probably to his daughter)

I picked up an Enfield back in 2007 (never fired it)

Last year I traded my buddy Mike some ammo to de-cosmoline it for me. :)

Earlier this year I picked up some 303 Brit dies.

Tonight I finally loaded up some 303 Brit ammo.

12 years later.... I have 30 test rounds ready to shoot. Using 174gr Hornaday Round Nose. Two different test loads; one IMR-3031 and one H414.

I'm not a procrastinator or anything.

I'm just slow.

I call it the "dozen year plan to finally shoot a rifle".

I have five Enfields, and they don't like boat-tailed bullets, they'll keyhole every time. They seem to prefer flat-based bullets. Just sayin'.....
The Dozen Year Plan ... I like it.

Sounds like you are also a proud non-member of the Instant Gratification Society, unlike most others in this country.

O'course, per some of your posts, you have been spending a LOT of time with you PS90(s), among others. ;)

I still have about a dozen Enfields (Nºs 1,4,5) ... and, ayup, flat-base bullets are the way to go.

I haven't reloaded any in awhile, but, IIRC, the load that I settled on in an attempt the replicate MkVII Ball involved salvaged projectiles (out of Click-Bang milsurp) and IMR3031 (39-40gr?).
Yes I like modern guns, but I like old guns too. There's more purity in reloading for and shooting old guns. It's a different process for me. I did the loading old school and shut off the electric auto-dispenser when doing these. It makes for a more wholesome, intimate experience, and renews some techniques that I haven't used in a long time. :)

MKVII ball is 2440 FPS, according to the Sierra book. It can be done with 3031 if you push their listed max load up a little. Hornaday's book is a little more potent on loadings, but they don't list 3031 if I recall correctly, for that weight, anyway. Lyman and Sierra are about the same. All three mfg's used No4 Mk2 rifles for their load development. So there's no pressure data. (Not surprising).

I used Sierra data to start with, but plan on chronographing these loads to get the story from the rifle. I'll track the loads in a spreadsheet just like I do my precision bolt guns. I've heard Enfield bores are kind of like fingerprints, no two alike, so just like my precision bolt guns, I'll load to the gun, not the book. :)

For newer reloaders who would wonder why a person would exceed a listed maximum on an old gun; the listed data in the Sierra books are in blocks of 100FPS. A listed maximum means that "somewhere between this number and where the next number would be you will hit max pressure".

Other books list an explicit "MAX" - but again on this rifle there's no PRESSURE data listed, so you know they just observed, that on THEIR rifle, this is where they A) found pressure signs, or B) filled the case to capacity with powder and didn't push forward with drop tubes.

Basically it's a flag to step it up slowly to and from that point and watch for pressure signs in the brass. On a big 30 cal case there's a couple grains of weight, between point A and point B. It may mean that listed max is on the nose, and you'll see pressure signs in your rifle at that mark. But generally I've found this is not true, you can go a little higher than listed, until you start to see pressure. In this case to hit the spec with 3031, you're "40% to the next step". No two rifles will be the same and the rifle won't answer if you ask it, even nicely, so the only way to find out, is to try, and observe.


Other tricks exist for "modulating pressure". On my 300 Win Mag, for instance, I can increase case capacity slightly as I know precisely where my lands are, and I can load the bullet out to them. Pressure will slightly decrease as you move the bullet forward in the casing, for any given volume of powder, and then sharply increase again once you start touching the lands of the rifling. Each bullet type (mfg/weight/style) has a different shape so each one has to be figured out on it's own.

Bore matters as well, especially on old guns which weren't machined off of highly precise tolerances. Was the reamer used on my rifle the precise same size as another guy's? Was it worn down? Has the bore's rifling been worn? Has the throat eroded? Is the bore truly centered in the barrel? Is the bore curved? (It happens that sometimes there's a slight curve in some older barrels)

All of these questions - and the answers to them, affect how your bullet goes down the barrel, and will also affect pressure.

Anyway enough of a lecture for one day.
Last edited:
The .303 British is easy to load for. I have found IMR 4064 to give the best accuracy from my scoped no. 5. They are hard on brass. You need to get a broken shell extractor and stay away from S & B brass, and neck size only.
I "feeler gauge" check all my .303 brass regardless of how many times I have loaded it. I've come closer to having brass separate than I like to think. But Lee Enfields are really fun rifles.
Love my Enfield and was on same plan. Bought one as a teenager twenty years ago from Roses's for $59 and took it apart to sporterize. I know, I was young and wouldn't dream of doing it nowdays...but can't turn back time. Well it stayed apart for twenty years and this year I put an ATI stock on it and coat of duracoat. Harvested two bucks with it already using 150 gr SST .312 bullets being pushed by 4064. Pick it up over my modern rifles everytime I head out. Groups less than an inch at 100. Old rifles rock and it's already earned the title - meat gun.
Interesting on the o-ring usage to help get the rounds indexed to your chamber/headspacing. The brass I'm starting with is RP and WW that's about 30 years old. It has a beautiful dark, almost copper color, that I'm really not wanting to polish off. Will try the ultrasonic cleaner on a few after I choot'em, to see if they keep the oxidated look. First time I've ever had brass I didn't want to shine up. :)
Not open for further replies.