I am thinking about converting a .338-.378 Wby Accumark to a .416 Rigby 23" w/ iron sights and Tally mounts. Since I am not planning on any other shooting position but upright does anybody see any buffalo hunting problems with this rig?

Unless I'm mistaken, the rim diameter is smaller on the Rigby case . That might present some problems. But, I'm not a gunsmith so I can't say for sure. It would be easier to convert to the .416 Weatherby. (Same rim size as the .338-.378) Then load the .416 Weatherby down to standard .416 Rigby velocity.

-Bob F.

Well on this site, the ONLY major problem is that it is a MkV Weatherby (read not CRF).

Other than that oughta work otay. You got something against belts, or is there another reason for not going with a 416 Weatherby?

ASS_CLOWN

quote:

Originally posted by drdlongshot:
I am thinking about converting a .338-.378 Wby Accumark to a .416 Rigby 23" w/ iron sights and Tally mounts. Since I am not planning on any other shooting position but upright does anybody see any buffalo hunting problems with this rig?

Be my guest, but I don't know if that bedding block can take the pounding.

Also, as Bob said, a .416Wby would be a simpler conversion, and you can run it at 2400fps.

You may want to get the floorplate that increases your magazine capacity, too.

George

Why create a bastardized Mark V which will have very little resale value when you can get this:



It a Dakota in 416 Rigby with Talley mounts. Since the rifle has been for sale for a while, I bet a deal could be made.

Weaterby have an Accumark stock which they list separately for the 378 and 416. However, my guess is that is only because the 378 and 416 barreled actions have a second recoil on the barrel about inch out from the action and the Accumark stock has been altered so the 378 or 416 barreled actions will fit.

If it was me I would do the 416 Wby and for a couple of reasons. One is just that it is a Wby rifle and also you can be sure of no conversion problems and be sure everything works.

Secondly, if the gunsmith can get the 338/378 barrel off without wrecking it you can have what amounts to a switch barrel rifle and they could also share brass. You can take 338/378s up to 416 or 416 down to 338/378 as long as you do it in two steps. In other words it needs to become a 378 on the way through otherwise the Wby shoulders usually collapse.

The contour of your Accumark barrel is the same as what Weatherby use for the 416 except the 416 is not fluted.

If you are hung on having it as 416 Rigby you would need to check out rim diameter as Bob F as suggested and also rim thickness. Feeding should be simple as the 378 based Wbys have a vertical stack in line feeding magazine.

If the 416 Rigby has a thinner rim then I would stick with 416 Wby. The reason for that is Wby actions have poor primarary extraction because of the 54 degree bolt...that is the distance the bolt moves back while lift the bolt handle...and if the case rim in thinner on the 416 Rigby then some of your primary extraction is wasted because of the addition gap between the extractor and case rim.

Mike

500,

If he does it in 416 Wby he is not really creating a bastardized Mark V as Wby do offer exactly what he is talking about, that is, an Accumark in 378 or 416 Wby.

Mike

500,Nice rifle!!!!

500
I take it the Dakota is yours since you posted the photos. What is the price?

Well, you guys have been a big help. I will stay with the .416 Wby change. I will probably only use the gun on one trip and thought it would be easier to convert rather than start over with a new gun and all the tuning. Also, resale would be better. I do like the Wby. stock design with the reverse comb pitch for heavy recoil.