Thread: Looking for load data for 303 british

I have ordered some Hornaday (7.62 x 39 255 grn sub-X Projectiles ) they are measured at 0.3115 inch and i am wanting to try them in my 303 No4 Mk2, full wood, and a BSA P14 (straight bolt sporting rifle) both have brand new barrels and very tight head spacing. My pwoders are AR2206H, AR2209, H380, IMR4831, IMR4350 I have new Winchester and Bertrim Cases and 0nce fired PPU cases. I would like to know of a starting load, both barrels are 1:10 twist I am keen to see if they will stabilise in these rifles Have load data for 215 grns Cheers Gary

Haven't got any sorry BUT suggest if you plot your 215grn data against 180 grn data the difference is 35grns so add projectile weight= minus powder weight. The difference between what they are will be close enough to next step up in weight.... Give you starting point anyway,I'm guessing your looking to run subsonic or close to it??? So possibly 308 data will be very close... You should find data for that weight and be able to cross reference etc to work it out.

Good luck. They are only barely stable in some 1:9.5 twist barrels. I think you'll find them to be annoyingly sideways out of your Enfield if you are only wanting to push them subsonic.

I don't think anyone you'll find on a forum is suitably qualified to give you a starting load. But there are instructions from Hodgdon on how to use H4895 (AR2206H) for reduced loads, starting at like 60% case fills. This will probably still be supersonic though. Trail Boss would be the foolproof choice for subs, if you could find some. In lieu of that, you might have to experiment with something like Red Dot or Blue Dot.

Greetings,
The Hodgdon reduced load data is based on 60% of listed maximum load for the cartridge and projectile and not case capacity. For Trail Boss the start load is 70% of case capacity. You would be wise to read the Hodgdon work sheets from the website before starting. The real danger of reduced or sub loads is sticking a projectile in the bore. This is bad enough but things go downhill really fast if another round is fired without noticing.
GPM.

I wouldnt use any of the powders you have there, you won't get under the speed of sound if that is what you are trying to do.

Your best bet is AP70N if you can find it, and load it like it was Unique.
Otherwise you could try exploring AR2207 / H4198

I wouldnt use Trailboss for anything.

It would probably be SAFEST way to answer his questions all the same.it was Afterall made/designed for replacement of black smelly corrosive stuff in cowboy action shooting and the 303british was originally a black powder cartridge.

Thank you all for your replys, I am not looking for just sub sonic load, but just a safe load to start with and just to shoot targets to start with
Cheers Gary

Originally Posted by Micky Duck

It would probably be SAFEST way to answer his questions all the same.it was Afterall made/designed for replacement of black smelly corrosive stuff in cowboy action shooting and the 303british was originally a black powder cartridge.

No Trailboss has higher pressures. He would be better off loading 10 grains of AP70. At least we know that would work. But mainly it has no accuracy either in my experience. Its a horrible thing to use for anything except CAS shooting. Unique or AP70 on the other hand can be subsonic and also extraordinarily accurate.

Originally Posted by bowie1

Thank you all for your replys, I am not looking for just sub sonic load, but just a safe load to start with and just to shoot targets to start with
Cheers Gary

Yes I did wonder. These bullets you bought, you wanted to use them especially? Oh well.

If I had to shoot them I would try 40-42 grains of 2209. You couldnt get into too much trouble.

Originally Posted by bowie1

I have ordered some Hornaday (7.62 x 39 255 grn sub-X Projectiles ) they are measured at 0.3115 inch and i am wanting to try them in my 303 No4 Mk2, full wood, and a BSA P14 (straight bolt sporting rifle) both have brand new barrels and very tight head spacing. My pwoders are AR2206H, AR2209, H380, IMR4831, IMR4350 I have new Winchester and Bertrim Cases and 0nce fired PPU cases. I would like to know of a starting load, both barrels are 1:10 twist I am keen to see if they will stabilise in these rifles Have load data for 215 grns Cheers Gary

While I cannot help with a subsonic load, I use 43.5gr of AR2209 behind a 215gr projectile in 303 brit and. I get about 2100fps with it out of a 18inch barrel and it is accurate...(trajectory like a stone but accurate..) I do not know how the 255gr would fare behind that pressure wise,

The 30/06 uses 45gr of 2209 behind a 250gr to get similar velocity.

If you are want subsonic the you could start with a reduced load or ty some trail boss...

So wanting supersonic,it looks like you going to need to draw graph and plot it out. As said earlier the difference between projectile and powder weights pretty much end up as straight lines.you have already got three known weights so continue the line onwards.take that figure and proceed cautiously.

Originally Posted by timattalon

While I cannot help with a subsonic load, I use 43.5gr of AR2209 behind a 215gr projectile in 303 brit and. I get about 2100fps with it out of a 18inch barrel and it is accurate...(trajectory like a stone but accurate..) I do not know how the 255gr would fare behind that pressure wise,

The 30/06 uses 45gr of 2209 behind a 250gr to get similar velocity.

If you are want subsonic the you could start with a reduced load or ty some trail boss...

Ken Waters pet load for 303B IIRC, with 215gn Woodleigh bullets was 45.6gn of RL19 for about 2200 fps - but do the research and check this, I am not handy to my bookshelf at the mo. May not be relevant to powder you have but there has been some RL19 on offer recently I've noticed, FWIW

Originally Posted by Jhon

Ken Waters pet load for 303B IIRC, with 215gn Woodleigh bullets was 45.6gn of RL19 for about 2200 fps - but do the research and check this, I am not handy to my bookshelf at the mo. May not be relevant to powder you have but there has been some RL19 on offer recently I've noticed, FWIW

Thats very close to what I am doing with the 2209. I started in the middle of the min/max suggestions in the ADI book and got the above load. It worked very well. I figured that going to the max to gain about 100fps was not worth the trouble and dropping to minimum would only lose about 150fps. And the short barrel does not help.

As for performance...most of my hunting mates that have seen it in use nicknamed it the Hammer....every animal I have shot with it has been found right where it was when it was hit...like it was hit on the head with a hammer....Those 215gr woodleigh round nose hit HARD......I just have to make sure I hit it...(tried it at a target at 300m- got a very small group....38 inches low but small none the less....and that was inch high at 100)