Boolits too soft ?

[gerrycan]

Hi all,
A customer complains about his soft cast boolits keyholing at speeds towards 1800 fps. The proj,s are about 188grs gc for 303Br. at .313 . I,ll make them harder but he may lose expansion . Opinions please, Gerry.

[JeffinNZ]

I have a VERY accurate SMLE load consisting of a 178gr projectile cast in sub 10 BHN alloy that departs my company at 1900fps.

The keyholing is because the .313 is TOO small for his rifle IMHO. Both my .303's are tight at .311-.312 in the groove and the skinniest boolits I shoot are .314 but prefer .316 inch.

[Bret4207]

Fit comes first. Do the boolits fit the barrel and load? Is his barrel leaded or clean? There's a heck of a lot more to why a boolit key holes than Bhn.

[geargnasher]

I agree with Jeff and Bret. When a boolit keyholes, it has very little to do with hardness. One of those "end user" things. It's up to the loader to solve the problem, not the guy casting the boolits. It's the end user's responsibility to take groove measurements and advise you of the size he needs. If you can make the boolits .315" or so that might help.

Gear

[williamwaco]

Gerrycan.

I know only two causes of keyholing.

1) The bullet is not stable. It doesn't get spun by the rifling. This is a fit problem or a bad bore problem or a spin rate problem. Not a hardness problem. You need to take a look at some recovered bullets if you can get some undamaged ones.

2) The bullet is not traveling fast enough. I see this quite often with handgun target loads. Loads leaving the muzzle at around 700 fps may print in one inch at 25 yards and be tumbling end over end at 50 yards. ( This is NOT the problem your customer has.)

You do not mention how hard your bullets are but I get good accuracy from my .38-55 with 250 grain bullets that test 8 to 9 BNH at 1800 fps.

[cbrick]

BHN DOES NOT cause keyholing. Not way too soft. Not way too hard.

The only BHN problem he has is buying into the "hardcast" tripe.

Make the bullet fit the firearm.

Rick

[beex215]

i had key holing once and that was due to a very leaded barrel. no rifle engagement.

[waksupi]

Undersize, and under weight.

[JeffinNZ]

Undersize, and under weight.

There's a complaint you don't see much these days. [smilie=l:

[44man]

All correct answers but one thing missed and it could be the rifle just does not like the boolit design.
I have seen problems even with jacketed that the gun doesn't like.
Many here have accurate loads so I would look at the boolits they use. [smilie=s:

[Frank]

44man:

All correct answers but one thing missed and it could be the rifle just does not like the boolit design.
I have seen problems even with jacketed that the gun doesn't like.
Many here have accurate loads so I would look at the boolits they use.
Yeaho. Tell your customer he needs to do a throat slug. Then he can begin to think about what design and size to use. And tell him, hard is better, especially if there is misalignment. :coffee:

[gerrycan]

Customer[is always right] has slugged his bore "yu [sic] were right my barrel slugs at 314- etc ". I feel better but it was just as I suspected . Thanks to all , once again, Gerry.