Selecting a GC bullet

[AtlLaw]

Being fairly new to cast bullet shooting I need some educated opinions on selecting a 45 Colt bullet for use in my Winchester (Uberti) M-73 rifle.  It's 24 inch barrel slugged out right at .452 and I was hopeing to use Hornady 250 gr. XTP's for this deer season, but they are unavailable.     They are advertised as .452, which I believe is the correct diameter for a jacketed bullet.

In my 44 Mag RSB Hunter I selected and use the LBT WFNGC's and am very happy with their shape and accuracy.  Therefore I think a WFNGC would be a wise choice for the '73 in that it should function well through the rifles action and at 1200 or so fps be fine for deer.

Remembering that the bore of the rifle measures .452, if I were using unchecked bullets I would order them sized to .453.  The question then is, when you add the gas check do you still go by the general cast bullet rule of selecting a bullet diameter .001 or .002 over the bore diameter, or do you revert to the jacketed bullet practice of matching the bore diameter?

In other words, when using a gas checked bullet in a rifle with a bore measuring .452, do you select a .452 or .453 diameter bullet?

[Nobade]

No need for gas checks in any 45 colt load that makes safe pressure in a '73. Or jacketed bullets for that matter. Just use a fairly soft (like air cooled wheelweights) bullet, good lube (not the crappy commercial crayon kind), size them .001 or a little more over groove diameter, and shoot.

As a side note, my Marlin 1894 rifle, in 45 colt, has a HUGE chamber. It will shoot .452" bullets just fine, but suffers some serious blowback into the action. But loaded with .458" bullets designed for the 45-70, it is also super accurate and the case seals the chamber. In other words, bullet diameter doesn't seem to matter much as long as it's not too small, and the case can release the bullet properly. At least in 1000 fps 45 colt loads!

[jhalcott]

I'd go with a .453 dia bullet gas checked or not. Bullet fit to bore is most important for accuracy. Assuming this is the 45LC lever action model ,for RELIABLE feeding bullet style and over all length must be correct.

[Graybeard]

I've always sized all my .45 caliber bullets at .452" regardless if plain base or GC for the Colt or .454 Casull.

[jbquack1]

I would go with the rcbs 270 saa.it is a plain base,but at the velocities you are talking about,plain base is fine.

[AtlLaw]

Interesting...  There really doesn't seem to be a consensous.   

Oh well, I have a hundred unchecked RNFP's that measure .452.  I'll try them and see what I get.   

[zoner]

if you're planning on 1200fps out of your .45 Colt rifle just shoot a 250 or 300gr cast bullet without a gas check....you don't need em at that velocity

[Lloyd Smale]

you may not need a gas checked design at those speeds but to get away without using one everything has to be just right. bullet size, alloy, proper chamber, and a good barrel. Problem is is that that is rarely the case. 9 times out of 10 when the bullet speed gets about a 1000 fps i have better luck with accuracy with a gas checked bullet. Problem is there isnt to many gas checked bullets in that weight range that work well in a levergun. Lbt sells a few designs. Just make sure to specify that its for a lever so he doesnt make the nose to long for function. the 250 lee rf is a decent bullet in a lever gun but is a plain base and doesnt carry much lube. So if i was running it in a lever id cast it at least 15bhn, use a good quality lube and keep the speed to about 1000-1100 fps. As to size its going to be a matter of how your barrel and chamber were cut. theres a big variation in 45 colt specs and especially in guns like your 73. You will probably get your best accuracy with a bullet that is as big as will chamber reliably. Problem with that is a guy ends up having to buy a few dies. But thats not a bad thing as you will have them to try differnt sizes in differnt guns. to start with id buy a 452 and a 453. What this all comes down to is what your standards for accuracy are. If hitting a beer can at 20 paces is good enough then buy a plain based mold and a 452 sizer and live with it. If your a bit anal like me its going to take alot more.