Taper before or after?

[hoz53]

Ok I thought I remembered a thread about if it's best to taper a barrel before or after its rifled. Couldn't find it. So which one is it or does it matter? I'm thinking here about how it might affect accuracy. Thank you all for ur support

 

[JohnKielly]

As I've heard it told, button rifled barrels can change bore diameter if reprofiled after rifling; cut rifled barrels don't have that issue.

 

[johnfred1965]

As I've heard it told, button rifled barrels can change bore diameter if reprofiled after rifling; cut rifled barrels don't have that issue.

I heard the opposite, if you button rifle a profiled barrel, the changing diameter puts differing pressure on the button, causing varying depth of grooves. Cut barrels don't have that issue

 

[RWO]

Button rifled cylindrical blanks are stress relieved before profiling. That prevents the bore dimensions from changing.

RWO

 

[johnfred1965]

I heard the opposite, if you button rifle a profiled barrel, the changing diameter puts differing pressure on the button, causing varying depth of grooves. Cut barrels don't have that issue

Did some more research, the Lilja website said that button barrels "can" expand during contouring after rifling, "if" the barrel is not properly stress relieved after the rifling process. Lilja heat treats after rifling to eliminate these stresses.

more info here on button rifling: http://firearmshistory.blogspot.com/2010/05/rifling-manufacturing-button-rifling.html

don't know the blogger's credentials, but he seems to be in line with other sources

 

[mac86951]

I would think taper after in both cases to ease holding barrel during rifling. Stress relieve is a good idea, and watch feed / cut ra tes in profiling. I would think lots of lube and keep barrel / tool cool.

 

[savagedasher]

Did some more research, the Lilja website said that button barrels "can" expand during contouring after rifling, "if" the barrel is not properly stress relieved after the rifling process. Lilja heat treats after rifling to eliminate these stresses.

When it is done it seems to me would end up being the last process befor shipping . Larry

 

[hoz53]

When it is done it seems to me would end up being the last process befor shipping . Larry

Thanks Fellas. Interesting --so if button rifled barrels need stress relieved before profiling, I wonder if you buy a blank if it's stress relieved before you get it so you can profile it. Sounds like the best thing to do is buy cut barrels if I wanna taper them myself. Hoz

 

[savagedasher]

Thanks Fellas. Interesting --so if button rifled barrels need stress relieved before profiling, I wonder if you buy a blank if it's stress relieved before you get it so you can profile it. Sounds like the best thing to do is buy cut barrels if I wanna taper them myself. Hoz

You can get both un tapered . So it shouldn't matter . Larry

 

[Hippy]

I have One of the "Newer" Button process barrels WAAYYYYYYYYYYYYY Late on delivery date when I asked him about it this was his Reply " We are running 20 Cals right now should go in the oven for stress relieve Wednesday and be contoured in a couple weeks we have been slammed and have worked the last 3 Saturdays trying to catch up"

Jim

 

[DaveTooley]

Some cut rifled barrel makers contour before reaming to keep the reamer as close to center as possible

 

[hoz53]

Some cut rifled barrel makers contour before reaming to keep the reamer as close to center as possible

Hippy. It would be interesting to know who that barrel maker is. So your barrel is getting stress relieved. I think that is good. The wait time you bring up in one reason I'd like to taper my own barrels. Seems like you can get untapered blanks quicker at times. That plus they are cheaper so if a guy has the equipment why not do it yourself. Inless it would harm the accuracy potential. That's what I'm trying to find out.

Dave Tooley-- I Am trying to understand why tapering the blank first would cause the reamer to be/stay closer to center. Could you explain that a bit more as I'm new at this.


Thanks again Fellas

 

[swd]

Hippy. It would be interesting to know who that barrel maker is. So your barrel is getting stress relieved. I think that is good. The wait time you bring up in one reason I'd like to taper my own barrels. Seems like you can get untapered blanks quicker at times. That plus they are cheaper so if a guy has the equipment why not do it yourself. Inless it would harm the accuracy potential. That's what I'm trying to find out.

Dave Tooley-- I Am trying to understand why tapering the blank first would cause the reamer to be/stay closer to center. Could you explain that a bit more as I'm new at this.


Thanks again Fellas

Contouring barrels is about as fun as watching paint dry. Paying the barrel maker to countour them is cheap for the time it will take you!
But unless your building Benchrest rifles you probably won't notice any difference in accuracy. I've done my fair share over the years and they've always shot to my expectations.

 

[Phil]

I have a cut rifle barrel that is made by one of the BIG names in the barrel industry.

It was profiled from a cylinder to a heavy varmint by them, they said that they can usually go down 2 profiles but that depends on what profile they start with.

Best bet is to call the manufacturer and ask....

Phil.

 

[hoz53]

I have a cut rifle barrel that is made by one of the BIG names in the barrel industry.

It was profiled from a cylinder to a heavy varmint by them, they said that they can usually go down 2 profiles but that depends on what profile they start with.

Best bet is to call the manufacturer and ask....

Phil.

Thanks swd and Phil I learned from both of your posts Hoz

 

[DaveTooley]

Hippy. It would be interesting to know who that barrel maker is. So your barrel is getting stress relieved. I think that is good. The wait time you bring up in one reason I'd like to taper my own barrels. Seems like you can get untapered blanks quicker at times. That plus they are cheaper so if a guy has the equipment why not do it yourself. Inless it would harm the accuracy potential. That's what I'm trying to find out.

Dave Tooley-- I Am trying to understand why tapering the blank first would cause the reamer to be/stay closer to center. Could you explain that a bit more as I'm new at this.


Thanks again Fellas

The blank is drilled and the drilled hole is not centered when exiting the other end. Turning balances the hole with the blank and as much as possible centers the reamer eliminating centrifugal force trying the throw the reamer off center creating an egg shaped hole.

 

[hoz53]

The blank is drilled and the drilled hole is not centered when exiting the other end. Turning balances the hole with the blank and as much as possible centers the reamer eliminating centrifugal force trying the throw the reamer off center creating an egg shaped hole.

This has been interesting to me for sometime as I've wondered how they got the hole centered on both ends when we know none of them are drilled absolutely strait all the way through the blank. It just seems like they would drill the blank before profiling so if the hole comes out on the far end a little off center then when it is turned on centers in the bore that would even out the material on all sides of the barrel to the center of The bore. Is this right or am I thinking about it wrong? Do you mean the blank is drilled, then profiled and then reamed-rifled? This makes the most sense to me. Thanks for your patience. Hoz

 

[IdahoSharpshooter]

Hey Dave! Got any 30 American brass left?

 

[DaveTooley]

Hey Dave! Got any 30 American brass left?

May be 3 or 4 pieces.