Going from 7mmRM to 7STW in a parker-hale?

[brasscollector]

Might get a Parker-Hale in 7mm RemMag. What I've really been thinking about is a 7mmSTW. Doing a bit of looking around and I've read quite a few people have had good results going from the 7RM to the STW, and it seems like a fairly simple re-chambering.
My question is whether the parker-hale action is going to accommodate the larger cartridge? I have no hands on experience with the Parker-Hale action. My experience with controlled feed actions (i.e. a model 98) is that the cartridges absolutely need to feed from the magazine.

 

[eastbank]

98,s are made for war and that is a must when your life may depend on it, but you can have the extractor beveled to close on a single loaded cartage. I can,t help you on the strength of the PH action.

 

[Nature Boy]

My experience with controlled feed actions (i.e. a model 98) is that the cartridges absolutely need to feed from the magazine.

That’s not necessarily true.

Anecdotal evidence to follow:

I have 3 CRF/Claw extractor actions. One has 3k rounds through it. I’ve never loaded a single round from the mag. Every round was top loaded one at a time. Not a single jam or failure. Another of my CRF rifles has over 6k rounds through it. A conservative guess is maybe 100 have been fed from the mag. Same results. No drama. My third CRF action is more of a hunting rifle so I use the magazine, however, the bulk of the rounds fired through it are for load development and every one of those was top loaded, single fed, extractor snapped over the rim, into battery and BANG. No problems

As I say, that’s personal, anecdotal experience but it’s several thousand data points across 3 rifles so take it for what it’s worth

 

[MachIVshooter]

7 STW has nearly the same MAP and the same rim diameter as 7mm RM, so bolt thrust is virtually identical, ergo action strength is not an issue. Unless the barrel profile precludes the deeper reaming, it'll be just fine from a safety standpoint.

If your rifle doesn't have a magnum action, obviously using the magazine is going to be a problem. I personally would not want to turn a magazine fed hunting rifle into a single shot, but that's for you to decide.

Perhaps the elephant in the room is the matter of whether the 7 STW affords an advantage you need that justifies the conversion cost and the scarcer, more expensive ammunition. If I had a 7 RM rifle, I could do the conversion for the cost of reamer rental, but I wouldn't. 7 RM is adequate for any game on this continent at greater range than most people can ethically take the shot.

 

[brasscollector]

@Nature Boy That is a good point. I've only messed around with a couple of 98s and both were military actions. I still have one of them and it will not single feed but it is a hunting rifle and I feed from the mag anyway.
If it's not feasible to make it feed STW from the mag I may forego the concept altogether as it would not be a bench gun for me.
I'm of the understanding (i.e. I could be wrong) that the P-H actions were refurbished milsurps which would make the 7mmRM about the longest round that it could feed from the mag. If that's the case I might be barking up the wrong tree.

 

[LoonWulf]

7 STW has nearly the same MAP and the same rim diameter as 7mm RM, so bolt thrust is virtually identical, ergo action strength is not an issue. Unless the barrel profile precludes the deeper reaming, it'll be just fine from a safety standpoint.

If your rifle doesn't have a magnum action, obviously using the magazine is going to be a problem. I personally would not want to turn a magazine fed hunting rifle into a single shot, but that's for you to decide.

Perhaps the elephant in the room is the matter of whether the 7 STW affords an advantage you need that justifies the conversion cost and the scarcer, more expensive ammunition. If I had a 7 RM rifle, I could do the conversion for the cost of reamer rental, but I wouldn't. 7 RM is adequate for any game on this continent at greater range than most people can ethically take the shot.

shoosh you stop being sensible! of course he needs an STW!

I'm kidding, I've done the STW conversion, but my 7RM had a wierd lop sided neck cutting it to stw got rid of that....gained an easy 200fps with 162s also, again not that I really needed it. Brass was made from 300wby cause I could get it, and stw or 8mm RM was unobtanium at the time.

 

[MachIVshooter]

Brass was made from 300wby cause I could get it, and stw or 8mm RM was unobtanium at the time.

Yeah, I have a 1978 BDL in 8mm mag, and I'm glad I grabbed a couple hundred pieces when I could, because Remington only seems to do runs about once per decade. Same with my .350 mag.

 

[troy fairweather]

My lgs has about 10 boxes of 8mmrm if I had a rifle to use my reamer I'd try to pick them up.