Tuck Posted January 7, 2014 Report Share Posted January 7, 2014 Hi all perhaps one for the gunsmiths on here, if they would give me there opinions I would be very greatful, I have two rifles both on tikka 595 actions and quite like the idea of them sharing a stock as they are never used together, but one has swamped magnum sporter weight barrel the other a target Palma barrel I would like to Have the Palma re profiled to match the swamped barrel there is plenty of meat on the Palma barrel just wondered would this viable? And is it easy to match a profile when turning down a barrel, I know it will need re proofing and no guarantee to keep it's accuracy but a risk I'd be willing to take. Any input would be helpful...... Link to comment Share on other sites More sharing options...
Grouse Posted January 7, 2014 Report Share Posted January 7, 2014 Baldie did a similar profile barrel match on my switch barrel 6br and 260rem. He would be my first line of enquiry... Link to comment Share on other sites More sharing options...
6.5shooter Posted January 7, 2014 Report Share Posted January 7, 2014 For the cost of doing this it might be worth just getting another stock. Link to comment Share on other sites More sharing options...
trucraft Posted January 7, 2014 Report Share Posted January 7, 2014 Mik at Dolphin could do it. If he doesn't have your barrel profile on the computer he can program a custom contour for an extra charge. I would give him a call. Link to comment Share on other sites More sharing options...
furrybean Posted January 7, 2014 Report Share Posted January 7, 2014 Steve Bowers has just done it for me and did a first class job! Link to comment Share on other sites More sharing options...
Chris-NZ Posted January 8, 2014 Report Share Posted January 8, 2014 The viability of turning down barrels (ignoring the cost) hinges on how the barrel was made. If it's a cut rifled tube, should be low risk. If it's buttoned or hammer forged, there is some risk the bore dimensions will open up unpredictably after it's turned down. This happens because the stresses are released when reducing the external dimensions. I'm not saying you're wasting your time with the latter two types but there's a definite risk they won't shoot as well after being reduced in diameter. Link to comment Share on other sites More sharing options...
baldie Posted January 8, 2014 Report Share Posted January 8, 2014 Never had any problem at all with either type. I have a rapidly depleting stock of border blanks that are unprofiled, they are then made to suit just what the customer wants. Link to comment Share on other sites More sharing options...
Chris-NZ Posted January 8, 2014 Report Share Posted January 8, 2014 Are these all their cut rifled "Border" or some Archers as well Dave? The lads here have def had problems slimming down TrueFlites when a small diam is requested Link to comment Share on other sites More sharing options...
Tuck Posted January 8, 2014 Author Report Share Posted January 8, 2014 Hi Chris And thanks to everyone who responded.. It wouldn't need go be made to thin it would be taken down to a magnum sporter profile around 0.650 at the muzzle, has anyone a approx costing as that will probably be the deciding factor Link to comment Share on other sites More sharing options...
Offroad Gary Posted January 8, 2014 Report Share Posted January 8, 2014 You going to be Prepared to check zero every time you swap? Would hack me right off, even when I was running r93's I ended up with a complete rifle in each calibre, and they would return to zero after swapping. Just an unnecessary ball ache. Link to comment Share on other sites More sharing options...
Tuck Posted January 8, 2014 Author Report Share Posted January 8, 2014 TBH Gary I was hoping to get away without zeroing every time as I assumed swapped over and torqued up to the same lbs each time I was hoping poi would stay the same? I'm not familiar with the Blaser system but doesn't that involve swapping barrels? I only want to be able to swap stocks, I often take the action out of the stock now if Iv been out in the rain, and put back in torque up and Iv had no issues with poi changing. So I just assumed I would be able to swap them over? Link to comment Share on other sites More sharing options...
baldie Posted January 9, 2014 Report Share Posted January 9, 2014 Are these all their cut rifled "Border" or some Archers as well Dave? The lads here have def had problems slimming down TrueFlites when a small diam is requested Mainly archers Chris. Have also done truflites in the past too. Never done one to a sporter profile though. They have always been rem pss or fatter. Link to comment Share on other sites More sharing options...
bradders Posted January 9, 2014 Report Share Posted January 9, 2014 The viability of turning down barrels (ignoring the cost) hinges on how the barrel was made. If it's a cut rifled tube, should be low risk. If it's buttoned or hammer forged, there is some risk the bore dimensions will open up unpredictably after it's turned down. This happens because the stresses are released when reducing the external dimensions. I'm not saying you're wasting your time with the latter two types but there's a definite risk they won't shoot as well after being reduced in diameter. I'm not a believer of this. All barrels are profiled after boring and rifling, no matter what method is used Link to comment Share on other sites More sharing options...
Chris-NZ Posted January 9, 2014 Report Share Posted January 9, 2014 Well you clearly haven't seen buttoned ones taken down to very slim dimensions. There is high demand here for lightweight barrels (read: high mountains) and I personally know two gunsmiths who refuse to do this sort of job after having obvious dimensional changes and serious accuracy deterioration from doing it Link to comment Share on other sites More sharing options...
bradders Posted January 9, 2014 Report Share Posted January 9, 2014 Well you clearly haven't seen buttoned ones taken down to very slim dimensions. There is high demand here for lightweight barrels (read: high mountains) and I personally know two gunsmiths who refuse to do this sort of job after having obvious dimensional changes and serious accuracy deterioration from doing it As opposed to seeing cut/broached/hammer forged ones taken down to very slim dimensions? Link to comment Share on other sites More sharing options...
Chris-NZ Posted January 9, 2014 Report Share Posted January 9, 2014 Yeh, I was specifically asking about buttoned ones. Link to comment Share on other sites More sharing options...
.308win Posted January 10, 2014 Report Share Posted January 10, 2014 I'm not a believer of this. All barrels are profiled after boring and rifling, no matter what method is used And then final lapped Link to comment Share on other sites More sharing options...
dannywayoflife Posted January 10, 2014 Report Share Posted January 10, 2014 As mark says surely all barrels are first rifled and then profiled? So surely more profiling won't damage them in any way or else surely they'd be duff in the first place? Link to comment Share on other sites More sharing options...
bradders Posted January 10, 2014 Report Share Posted January 10, 2014 As mark says surely all barrels are first rifled and then profiled? So surely more profiling won't damage them in any way or else surely they'd be duff in the first place? Yep Link to comment Share on other sites More sharing options...
Chris-NZ Posted January 13, 2014 Report Share Posted January 13, 2014 (Been away fishing) That statement isn't actually correct. It is true for button rifled barrels that must be rifled whilst in cylindrical form. There are various cut rifled barrels that have the rifling done -after- profiling. Two examples that illustrate the stresses in buttoned barrels from post manufacture thinning, both involving TrueFlites: - my gunsmith has seen various TF barrels that have been fluted by TrueFlite themselves. They didn't shoot and slugging suggested why. The internal diameter opened up noticeably at the start of the fluting and reduced back to std diameter at the muzzle where the fluting stopped. - he had to sort out a TF in .300WM that someone had fitted a suppressor to using a 1/2" UNF thread!. It wouldn't shoot for sh*t despite accurate threading and all the usual things like rear clearance checked. Measuring revealed the bore was belled at the muzzle at least a thou. It was cut back and another can with more suitable thread diam fitted. The thing was very accurate after this. Both these go to show that internal stresses in buttoned barrels do exist and can show their nasty head with diameter reduction. They may also suggest that TFs stress relief processes may be less than optimal. Link to comment Share on other sites More sharing options...
bradders Posted January 13, 2014 Report Share Posted January 13, 2014 I've yet to see any barrel Mfr that's capable of deep hole drilling be good enough to drill a straight hole and get the bore within .005" of the muzzle and have minimal runout. In other words, no matter what type of rifling is done, all profiling is done after boring and rifling Link to comment Share on other sites More sharing options...
Chris-NZ Posted January 14, 2014 Report Share Posted January 14, 2014 I wasn't alluding to that sort of runout, ie the bore being eccentric to the exterior axis. The gunsmith gauged the barrel's internal diameter from the muzzle (in the second example) and could clearly measure the bore had "stretched" markedly in the region of the threading. This can only happen by the release of stress from reducing the external diameter significantly. For your information, both Broughton and Brux rifle their barrels -after- profiling. Have a look on Brux' website if you don't believe me. Link to comment Share on other sites More sharing options...
bradders Posted January 14, 2014 Report Share Posted January 14, 2014 So in other words, it doesn't really matter. BTW I've had several barrels where I've had to change pilots after starting chambering them as the bore has had tight spots. The thing is, the bullets and gun don't care, at 2000mph and 260,000rpm, velocity and centrifugal forces pay no attention to these mere things Link to comment Share on other sites More sharing options...
Chris-NZ Posted January 14, 2014 Report Share Posted January 14, 2014 Bullets actually do care a lot if they have to travel down highly variable diameter bores and they particularly are affected by belling of the bore at the muzzle. To repeat, the accuracy of that .300 WM with the 1/2UNF can thread was -appalling- but was fully fixed by simply changing to a sensible size. This is proof (amongst myriad other local examples) that TF barrels at least retain significant residual stresses from buttoning and you ignore that at your peril if you decide to thin the barrel markedly at any point, either by deep fluting or using a very small can thread size. My main gunsmith (who built the National winning F-Class rifle last year) has sets of pilots in one thou increments for a whole range of calibres. He is extremely fussy and it shows in the results they achieve. I don't mind a sensible discussion but I would have thought you could have at least have the decency to admit your strong assertion that I was wrong on profiling was wrong. Changing the subject isn't the way to deal with it Link to comment Share on other sites More sharing options...
bradders Posted January 14, 2014 Report Share Posted January 14, 2014 Now just a cotton pickin' minute Mister, no one ever said that. This thread is/was about reprofiling barrels. I've never mentioned fluting as far as I can remember. I said all barrels are profiled after the internal work is done....unless there's something someone isn't telling me. I don't believe in all the other myths, coz that's what they are...myths Link to comment Share on other sites More sharing options...
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