So I was shooting my 303 savage today with 150 grain berrys bullets today with 748 powder which shoots well but dirties the cases on the outside a bit. I had reduced my load of 32 grains to 30 thinking I only needed that for my savage 99 plinking. After about 4 shots I got a blast of gas in my face. I never shoot without glasses and was unhurt. The case came out black. The charge was too slow to seal the chamber and gas came back around it before the pressure built up. case was undamaged and the report seemed normal and the bullet hit the target. I had put magnum primers because I knew the charge was a bit low but it didn't seem to make any difference. I am going to change powders for my lower power loads in this rifle.
303 savage blowby
- Thread starter porpoise
- Start date
Perfect.
3031/4198 would be great choices
I've also used Rel 7 with good success in light loads, with 150 grain bullets in the 303 Savage.
Are you full length resing your cases??
I only partially neck resize the 303 Sav cases, because they can be very difficult to find and it helps with the situation you described.
The 303 Savage has a very long neck. One calibre of resizing is more than enough to hold the bullets in place and creat enough pressures.
I know about trail boss but don't want to go that slow. I have tinstar which is the same idea but not so extreme as trailboss.looking in my loading books it looks like 4198 might be a better choice for what I want to do than 3031 so I loaded some with 20 grains of it with my 150 gr. Plated bullets, haven't tried it yet. I suppose I could back off my full length die a bit
5744 can be difficult to find at the most plentiful times. I agree, it's bulkier and it's almost exactly the same burn rate as 4198
OP, if you have it, 2400 with appx the same weight of powder, under those 150 grn Berry's will definitely solve your problems.
I've used this load, under 160 grain powder coated bullets in a 30-30, had to go look for the book.
20 grains of 2400 over CCI 250 primers, under 160 grain powder coated cast lead = appx 2000fps out of a 303 Savage 99 I have in my safe.
Accuracy was very good, in that rifle, from what my records say.
I almost forgot to add, if you're only shooting those bullets out of one rifle, neck resizing only can be very beneficial to accuracy as well as making brass last almost forever with such mild loads.
A one caliber neck resize is exactly what I do for my rifle. Some of the cases have over a dozen reloads on them, with only one re annealing process
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5744 is closer to 4227 speed than 4198. Canada Ammo was selling D5744 since last spring. 2400 is a good reduced load powder if you can find it.
My 20 gr. 4198 loads turned out a bit fast at 1920fps, above what berrys recommends and shooting a bit higher than my sights allow for. They shot OK but I will be moving to n110 powder rather than reduce the 4198 more, although it seemed to give good pressure and no sooty cases. I like n110 it's a great reduced load powder it's a stick powder and I think is much like 2400 by the burn and loading charts although I have never tried 2400
i loaded 14.5 gr. N110 for a little over 1500 fps. It gave me this 2and 3/4 inch 5 shot 100 metre group a little higher than my 748 loads. I think i will add a grain and a half and it should be good. I see the top pic turned out sideways, the bullet holes should be at the top
