Thread: Subsonic 303

Hi there folks, 1st timer here. I'm having trouble getting a subsonic load in a .303 (10 inch twist) to pump out heavy (220 grain) lead bullets without tumbling.
I'm using 7.8 gr of shotty powder, cronoed at 960 fps.
Any help would be most welcome.
Thanks.

What's the bore like, have you slugged it to get the diameter. I've got 3 and only one will shoot cast bullets and they have to be paper patched. Even a buggered bore will shoot metal jackets ok, they seem to be fussy things with cast bullets

To tell you the truth, it's got plenty of meat but a bit pitted.

To tell you the truth, it's got plenty of meat but a bit pitted. I was reading elsewhere that someone makes new barrels for them,but is the cost worth it?

I have tried cast pills with trail boss out of a few enfeilds, worked in under half of them-reading Marty Henry's post makes me think I should try again.

There are a couple of places that make replacement no4 barrels but I personally doubt it's worth it for a sported hunting gun as for the fitted price you could buy a new budget rife from a few makers

True flite make .311" barrels but by time the you have it fitted you will be out the price of a good second hand .308 which is a better subsonic calibre,
Most .303's are not suitable for cast bullets at any speed generally the barrels are well worn and pitted, lead bullets don't mind worn barrels
but they hate pitted ones, your barrel sounds like it is over sized most of them are, the spec's are for a .304"/ .313" barrel most are .304"/.314" or bigger,
What diameter are the lead bullets you have tried? Robert.

No its not worth it , if you want to run heavy 30 cal bullets at subsonic velocity , just go and buy a Ruger Ranch rifle in 300 BLK , its got a 1-7 twist , so as to stabisle the heavy bullets at subsonic speeds .
It will be way cheaper .

I use 11.5-13 gns of trailboss depending on which rifle I'm loading for
Really only for plinking at 100yds
trailboss and a gas checked 220gn projectile is the best combination I've trialled
I don't like the thought if using fast burning pistol type powders

The bullets are what ever a 303 die squirts out. I would think they are 311.

What is a BLK?

Originally Posted by Rocky

What is a BLK?

https://en.wikipedia.org/wiki/300_AA....62%C3%9735mm)