303 Brit - 200gr cast

I

I Dont Care About You

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Experimented a bit with some 200gr cast bullets in 303.

4227 19.0gr - 1635 fps SD 5 fps
Blue Dot 15.5gr - 1644 fps SD 21 fps
Trailboss 11.0gr - 1210 fps SD 7 fps

Gonna try 12.0gr Trailboss and see if that velocity can be bumped up a bit.

I fairly impressed with the consistency of the 4227 and Blue Dot loads.
 
I do not know what powders you can find where you are? On Internet and various magazines, Mike Venturino uses bullets from Lyman mold #314299 and AA 5744 powder in 303 British. I got an Accurate Mold - 31-200L - "inspired by Lyman 311299 / 314299". Bullets from wheel weights come out for me at 207 grains / 208 grains (lubed and with gas check) - I ran them through .314" sizer - used "Felix Lube" from Internet, and installed Hornady (?) gas checks. Did not even check velocity - just wanted something that I could make here to fire 303 British. Seems to work fine for that. Back in the day, I got a couple containers of the AA 5744 powder - not even certain if it is made any more.
 
I Dont Care About You said:
How much 5744 are using under your bullets? I have access to a 4lb jug of 5744. ;)
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Lyman Cast Bullet Handbook - 4th Edition - lists 21.0 grains as Start load with Lyman #314299 mold bullets - at 1,566 fps, then Maximum load of 27.5 grains for 1,942 fps. They did use a gas check and sized those bullets to .313". Remington cases - trim-to-length as 2.212" - Federal 210 primer - rifle used for velocity only testing was Lee Enfield No. 1 Mk III* - listed as 25 1/2" barrel, 1-10" twist, apparently that barrel had groove diameter of .313". Is no mention on that page what lube they used on that bullet - might be listed elsewhere in that book?

To quote from their write-up on page 172 - "Accurate's 5744 and IMR's SR-4579 gave very good results in our testing". In that table for Lyman #314299 bullet loadings on p. 172, they indicate that "potentially" most accurate load was 18.0 grains SR-4759 for 1,561 fps. Is no pressures given for any loads - Start or Max - for any cast bullet weight shown on p. 172.
 
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Best accuracy and velocity I found with heavy bullets in .303 was with IMR/D4198. Pretty much any shotgun powder works well for low (under 1500fps) velocity.
 
B said:
Best accuracy and velocity I found with heavy bullets in .303 was with IMR/D4198. Pretty much any shotgun powder works well for low (under 1500fps) velocity.
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I found a couple of references for IMR 4198 under 180gr cast bullet. 18gr 4198 with a 180gr cast bullet and also IMR 4198 with a start load of 21 grains at 1500 fps and a max load of 28 grains at 1950 fps.

Then another post stating not to use 4198 with heavy jacketed bullets at regular velocities.
 
Good point, I was not talking jacketed to be clear. H414/W760 is best for 215grn RN in my testing with a Jungle Carbine. As far as the 4198 and cast 314299/GC bullets 26grns gets me 1800fps with good accuracy. 28 put me to nearly 2000 but the impacts were more of a pattern than a group. I have never bothered actually measuring anything.
 
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B said:
Good point, I was not talking jacketed to be clear. H414/W760 is best for 215grn RN in my testing with a Jungle Carbine. As far as the 4198 and cast 314299/GC bullets 26grns gets me 1800fps with good accuracy. 28 put me to nearly 2000 but the impacts were more of a pattern than a group. I have never bothered actually measuring anything.
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Sorry, I don't know what a 314299 bullet is. Weight?

A bit of google-foo and it seems the 314299 is a little over 200gr
 
I Dont Care About You said:
Sorry, I don't know what a 314299 bullet is. Weight?
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Is a Lyman mold number - nominally 200 grains weight - should be roughly .314" when cast - depends a bit on alloy that is used. Has a "sister" mold - just slightly smaller diameter - #311299 - smaller one throws close to .311" I think. 314299 designed / used mostly for .303 British or similar; 311299 designed / used mostly for .308" (30-06, 308 Win) or similar.
 
Yup that's the bullet I'm using, cast from #2 alloy by another CGNer. I'm nearly out by now, finding that mold to buy myself hasn't been easy so I may try something else.
 
I cast my own with the Lyman 314299. The load I have been using for years has been 20grs of Alliant 2400 with any large rifle primers. It works well in any of my 20 plus 303’s. A lot of shotgun pistol powders where giving me vertical stringing. 2400 doesn’t.
 
I have a bunch of 200gr 0.313in bullets for the 303 Brit. I noticed that the casting book from Lyman, the 3rd edition has lots of shotgun powder for low velocity loads, mostly subsonic, the 4th edition has pulled all of those and only lists rifle powders at significantly higher velocities. I was hoping to find a load with titegroup as I have a bunch of it, but trail boss it is, until I run out of that stuff.
 
For slower loads, Trailboss is prob the best choice as it gives by far the best case filling. Tiny charges of fast burning pistol powders aren't good for consistency or accuracy and may even potentially be dangerous.
 
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