Bulets tumbuling 303 enfeild

[bushman]

Using lee bullets molds casting 311 bullets 160 grain tumble but when using factory bullets from speer or hornbee no problems. Does anybody have this problem? Do you guys know how it can be solved? Thanks guys!

[Ford SD]

we need more info
rifle 303 model ?
powder & charge weight
bullet or mold it came from
what range is it tumbleing 50-100-200 ?

[longbow]

Without knowing more, it is difficult to say for sure but right off I have to note that 0.311" boolits are likely much indersize.

Most .303's (at least in my experience) have groove diamters of at least 0.312" to 0.315". Doesn't seem to affect jacketed bullets so much but undersize cast will not work well. I have two Lee Enfields both with 0.314"+ groove diameter and others have posted with groove diameters to 0.317". Cast boolits should be at least groove diameter and preferably 0.001" or more over groove diameter.

If you haven't seen this site there is good info here:

http://www.303british.com/id37.html

Longbow

[dromia]

Slug your bore and determine the actual groove and bore diameters and then use a boolit that is 2 thou or so over groove diameter.

Also as has been said more information would be helpful, what velocities are you trying for?

[303Guy]

And of course you need to slug the throat end of the bore, not the muzzle. For your boolits to be tumbling, they must be stripping or skidding on the rifling. Interesting. I have experienced this tumbling and that at very close range. The bore was oversize and rusted and the rifling rounded rather than sharp. It was a machine gun barrel and I have a suspicion that's how the rifling was made? You may need to clean the bore and perhaps even fire-lap it. You might even try paper patching those boolits you have?[smilie=1:

I just noticed that you said "303 Enfield" and not Lee Enfield. Is it a Pattern 14 Enfield? It may have a two-groove barrel. A two-groove barrel is a bit tricky to use with cast.

As said, more info would be of help.

[northof58]

My 303 Longbranch (two groove barrel) will tumble the Lee .311 bullets yet shoot factory jacketed .311 bullets very well. I now paper patch the cast bullets and put them through a .314 sizer. This produces a good grouping.

[bushman]

Thanks guys that was a real help! espesialy from 303Guy! the powder was IMR 30-31, 35 grains and 165 grain bulet. tumbled at 50 feet. Factory bulets, fly true up to 100 -150 yards with no problems. Thanks fellas any help will be greatly apprecited!

[runfiverun]

slow them down and measure.

[knappy]

Using lee bullets molds casting 311 bullets 160 grain tumble but when using factory bullets from speer or hornbee no problems. Does anybody have this problem? Do you guys know how it can be solved? Thanks guys!

Ii would be to low in size slug your bore and get a mould to suit. 303 have A larger bore on some rifls no more tumbleing, best of luck.

[JeffinNZ]

.311! You are about 5 thou short on girth at least. I bet she is a 2 groove barrel.

[Shiloh]

.311 is more than likely too small. I size at .312 for the '03 and Krag.

Shiloh