303brit load question

[Handloader]

In june of 2008 I had the pleasure of obtaining a 303B 1907 SMLE. Any way I traded a wore out ruger MK2 old style for the rifle and used the money I got back to buy a small lot of supplies. Any way I did a half way job of cleaning the rifle at the time and shot JB's through it both factor and handloads. I then bought a lee mold and started casting. The load I used was a W-W case, CCI 200LR,13.9 gr of UNIQUE,155 CAST W/GAS CHECK. And this load I thought was good until I shot it a 50 yards 10 shots only one hit the paper. So I found the article on this site be C.E. Harrison and it stated that if you cleaned the bore of all fouling it would shoot cast as well as a rifle in perfect condition. Is there any truth to this at all? I have been working on the bore and am removing gunk from 60 years ago it seems. What can I do to remove all the fouling and gunk from the bore and keep it gone. Also in that same article it stated that 16 grains of 2400 was a universal load for military loads. Is this true if so what is the mas load of 2400 and will it require a gas check. So please help if you can.

GOD BLESS US ALL

Handloader

[Kraschenbirn]

Yep!! If you clean out all the accumulated crud and work up a load with a bullet properly fitted to your bore, you'll find your LE will shoot CBs as well or better than jacketed. Took me two evenings, a great gob of Sweet's 7.62 and a whole lot of patches to clean up my #4Mk1 but it was well worth the effort. How 'bout sub-1" @ 50M and under 2" @ 100M (if I do my part)? Last time I had it out, I hit 8 of 10 on an 8" swinger @ 200M...from the military prone position, using original iron sights.

The 1909 Argentine I'mnow working on is much the same story. Expended a lot of elbow grease cleaning up the bore but, first time out, it printed 1 1/2" 50M groups with fire-form loads using the recommended 16 gr. of A2400 under Lee 312-160 boolits.

If you're casting a fairly hard boolit, properly fitted to your bore, and keeping velocities down in the 1400-1500 fps range (or less), you can probably get by without a gas check. Push 'em any fast than that, you'll get a lot better performance and less lead fouling with chacks than without.

Bill

[atr]

Getting that barrel clean is a necessary first step. Took me forever to get my .303 Mk4 cleaned out.
But then the fun really begins....you are going to have to do alot of experimenting with different loads and sizing diameters to find the best fit for your rifle. I would suggest either slugging the bore to find the groove dia. Or, start sizing your boolits at 0.312" dia. and play around until you find the best combination of charge and sized dia.
KEEP ACCURATE RECORDS OF WHAT YOU ARE DOING: LOADS AND SIZED DIA. and if the loaded round was crimped or not...etc. / otherwise you will get frustrated. With the reduced load you mentioned I would suggest you crimp your rounds. Also, if you have alot of lub sticking to the bottom of your boolit you could be getting powder sticking to that lub which then wouldn't ignite uniformly with the result being round(s) with uneven pressure and lots of "flyers"
ONE last caution: reduced loads (13.9 grains of Unique) in a large capacity case such as the .303 invites double charging. Be sure you take a flashlight and CHECK the powder level of each case before you seat the boolit !!!
At 1500 fps or less and with a cast hardness equivalent to lyman#2 you shouldn't need gas checks....above that use gas checks.

[Boz330]

As everyone said clean the copper out of it first. I use an electronic bore cleaner the first time, it's much easier. With the SMLE there is a good chance that it will have a lot of throat erosion from Cordite, requiring an oversize boolit. My SMLE is that way and I couldn't begin to get nose on hits with the same boolit that shoots great out of my #4. A chamber cast might be in order to determine that.

Bob

[JeffinNZ]

If you do a search of the forum you will kind LOTS of info on the .303 Brit.