Winchester 92 44-40 and 200 XTP?

[HGunner]

Does anyone load the Hornady 200 grain XTP in a Winchester 92 44-40?

[Mikey]

If you are talking about the 200 gn xtp slug used in the 44 spl, and 44 magnum, it is not a good idea.  The bore diameter on the 44-40 is .427, unless yours measures out to .429 or better.  A .429 diameter slug down a .427 bore will give you lousy accuracy, if any at all, and should jump or spike your pressures noticeably. 
If you have slugged your bore to .429 or larger, as may be possible with original 92s, then you should be able to use the .429 diameter slugs.  If your bore slugs to .427 then I suggest you go with a proper diameter slug and for whitetail (if that's what it is for) I would suggest a cast slug, properly sized. 
There are round nose flat point cast slugs avialble for the 44-40, sized to the right diameter for your rifle and since those were quite capable of bringing home the venison I think I might avoid the cost of jacketed slugs and go with original loadings and the like. 

[HGunner]

If the .430 XTPs are too big would it be safe to resize the XTPs to .427 using a LEE sizer?  This would be a lot cheaper than buying the Winchester 200 grain JSPs (the XTP's are about $12 cheaper per 100).  I want to use the rifle for deer hunting this season.

[w30wcf]

Hgunner,
I have fired the 200XTP Hornady with no issues whatsoever in my Marlin '94 Cowboy which has a .428" groove. Sizing the bullet down .002-.003" when firing will raise pressures a little bit but way below what the '92W and 94M can handle.
Personally I like the  21/4759 recipe. It is a capacity load and replicates the early H.V. (High Velocity) cartridge of around 1,600 f.p.s.  It shoots very accurately.

Before you load any I would suggest making up one round to make sure it will chamber ok and the .430" diameter bullet did not make the neck o.d. too large to chamber.  Also, to keep the oal less than 1.60" with the XTP, you may need to trim your brass just a bit unless your '92 will chamber a longer cartridge from the magazine.

w30wcf
 
 

[Mikey]

Unless Marlin has finally gotten the bore diameters right the bores on their pistol cartridge carbines and rifles usually run oversize and it is not uncommon to find 44 magnum Marlins with bores in the .431 - .432 range, and 41 magnums running around .413.
Since Hgunner is shooting a Winchester 92 I feel he should still slug his bore to be able to maximize the accuracy potential of the rifle and caliber.  I don't usually take to sizing down jacketed slugs as even after sizing the often spring back to original diameter and the concern for pressure spikes or high pressures is as great as a loss of accuracy from oversized bullets.  The largest bullet I would use in the 92, without slugging the bore, is a .429.  I would not use a .430 bullet unless your bore mics out that much. 
And again, I wouldn't use jacketed slugs in that caliber.  The cast slugs for those rifles and revolvers can bring excellent accuracy if you and the rifle are up to it, and those slugs work just fine on Whitetail.  I think if you can find a older Lymna reloading manual, say a 43rd or 44th edition, I think you will be very surprised at what a 20" 44-40 can do.  Good luck.