75gr. .223 handloading

[JRiddle]

I bought some Hornady A-Max Moly  bullets 75 grain, but find them to be too long to work in my semi-auto rifles.  I just got a 14" .223 barrel for my Contender, I was going to try loading them for it.  Does anyone have any experiences or opinions on the heavier bullet in the Contender?  If someone has found a good load I'd be appreciative if you'd share, I've not been able to find much info.  I use IMR3031 for my current .223 loads, any opinions on that?  Thanks in advance for your input, and thanks to those who share so much good information here.

[KN]

Twist rate on a TC barrel is 1-12". Not nearly fast enough for a bullet that heavy. It will tumble. About the heaviest you can shoot from a factory barrel is 62grs, maybe. For that heavy a bullet you will need a twist in the range of 1-7".    KN

[Curtis]

I've never shot any bullet heavier than 55 gr. from mine.  I started out using 3031, but from a ten inch barrel there was too much muzzle flash and blast.  I read good reports from IMR-4198 and lighter bullets and now that's all I shoot.  Accuracy has been good with this caliber no matter what I feed it.  I don't have a chrono so I can't compare velocity between the two powders, but there is much less "fire and brimstone" associated with my shooting now.  I still keep some loads around using 3031 in case I want to "impress the locals".

Curtis