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wmitty
11-23-2008, 12:47 AM
Bought a new takeoff .375 H&H barrel along with a used 700 Rem in 7 mag with the intention of putting together a cast boolet shooter. I've removed the original barrel and used a depth mike to check clearances and dimensions on both the action and new barrel. The barrel needs to turn roughly 135 degrees to allow sight holes to align. My question is, can I reduce the thickness of the recoil lug by the .023" needed to allow sight alignment and then run a finish chamber reamer into the chamber to increase chamber depth back to correct headspace? Trying to do this without using a lathe, but I'll take it to a 'smith if someone sees a problem with doing it as I described.

HeavyMetal
11-23-2008, 01:01 AM
Are you planning to put iron sights on this gun? If so trim the .023 off the lug. If not, and the barrel sungs up with the correct headspace, just put a screw or two in the holes and be done with it.

Another thought is look at Brownells catalog. I know they offer lugs in several thickness's maybe you can find one that won't require any work?

Figure it's simpler to do some research before you do any metal removal.

Nobade
11-23-2008, 10:43 AM
I wouldn't recommend trying to thin the recoil lug. They are quite hard, and that much material removal would require a surface grinder. It has to be flat and parallel or it won't work. Not to mention that you must allow for draw torque, which you don't know since you don't know how flat your mating surfaces are (barrel shoulder, lug, reciever face). So it would be a cut and try proposition.
So, I would strongly recommend you getting it done correctly. You'll be much happier looking at your properly assembled and set up rifle in the future than if you just slap it together.

Scrounger
11-23-2008, 02:04 PM
Not a gunsmith but couldn't the same thing be achieved by removing that small amount .023" from the barrel shoulder?
Alternatively, I am sure there are variations in the thickness of recoil lugs. You could accurately measure the thickness of yours and ask if anyone on the forum has one that is .023 thinner than yours. Probably several guys have the lugs from barrels they have removed.
Now this one I'll get static on: You're talking almost half a turn here; you could go the other way to make your sights line up. You'd end up with a chamber that would be about .050" long in headspace. You could seat your bullets out a little long to keep the case head against the bolt face and fireform the brass for your chamber. Set reloading dies to match. Agreed, correcting the problem with a lathe would be the best solution, but if you had to do it, that way would work.

Phil
11-23-2008, 02:25 PM
Don't forget to allow for crush when you remove metal from the shoulder of the barrel. If you don't, the barrel will tighten over center. That's why its better to have the job done properly. Cheaper in the long run into the bargain.

Phil

wmitty
11-24-2008, 12:40 PM
The barrel is drilled/tapped for sights so the holes look pretty bad being so far out of alignment. I realize I could screw the barrel "out" to obtain sight hole alignment but I have a Model 70 .375 that I was hoping to share brass with.

I have a second recoil lug which measures .187" in thickness so there is a few thousandths variation in thickness of factory lugs.

Gentlemen, thanks for your thoughts on this. I believe I'll find a gunsmith who will set the shoulder back the .023" and then deepen the chamber to correct headspace.

johnly
01-12-2009, 12:32 PM
I have a 375 H&H reamer from an identical project a couple years back.

John

mroliver77
01-13-2009, 02:06 PM
Talk to Willbird on this forum. He does mighty fine work on 700 Rem.
J

Willbird
01-13-2009, 10:46 PM
Talk to Willbird on this forum. He does mighty fine work on 700 Rem.
J


And darn little of it too ;-)

Bill

wmitty
01-24-2009, 05:53 PM
I went ahead and barrelled the action to see how the rifle would shoot with cast as it is currently throated. (has a funnel shaped throat) and I was really disappointed.

I tried several loads which had shot really well in the M 70 and nothing I tried grouped worth dirt. It looks like I will now have to set the shoulder back enough to rechamber deep enough to get rid of the existing throat. Should I throat the barrel with a straight sided throat at groove diameter, which is .377" ?

Willbird
01-28-2009, 09:48 AM
Typically a throat is bigger than groove dia, if you do it right AT groove dia if there is anything the tiniest bit off center it will not clean up all the way around ? Your reamer will follow the old chamber unless the gunsmith bores it first, re-chambering is actually quite a bit more difficult than chambering in the first place....and the results are iffy....that is why a lot of people do not do it......their name rides on the quality of their work, and rechambering is a crapshoot in that dept.

Bill