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Old 10-22-2009, 08:51 PM   #11
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I moved the AR related posts to this thread guys....

http://www.firearmstalk.com/forums/f20/jds-personalized-advice-my-ar-thread-18669/#post175903

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Old 12-30-2009, 12:29 PM   #12
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Default Mounting a Tang sight on H&R

I'm prepping an H&R 45/70 Buffalo Classic for long range Cowboy Action Shooting. Does anyone have a suggestion for mounting a Creedmore tang sight on this? (There is no tang, only stock.)
Thanks for any input!

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Old 01-26-2010, 01:56 AM   #13
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Originally Posted by cpttango30 View Post
Don't forget a recrown job they don't cost much and can enhance accuracy of a factory rifle.

Care to explain how?
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Old 04-16-2010, 06:46 PM   #14
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Originally Posted by cpttango30 View Post
Don't forget a recrown job they don't cost much and can enhance accuracy of a factory rifle.
What exactly gets done during a re-crown job? Thanks
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Old 04-16-2010, 06:51 PM   #15
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Care to explain how?
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What exactly gets done during a re-crown job? Thanks
Essentially what you are doing is taking the last couple hundred thou of the barrel and trimming it back, at an angle, to give it a "crown".

This is a definitive, machined and clean END of the lands and grooves.

It's not uncommon, because the end of the barrel is banged or bounced during packaging or shipping or unpackaging or placing/removing from the display rack, for the slightest of damage to happen to the crown. If there is a tiny burr or scratch that can impede the bullet on it's rotation out the bore, it will affect it's flight and by way, it's accuracy.

What is done is the barrel is usually pulled from the action, trued up in the lathe and an angled cut is taken from the very end of the barrel. back enough to eliminate the existing factory crown and making a more sharp, crisp and pronounced end of the threads.

JD
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Old 04-16-2010, 07:11 PM   #16
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Essentially what you are doing is taking the last couple hundred thou of the barrel and trimming it back, at an angle, to give it a "crown".

This is a definitive, machined and clean END of the lands and grooves.

It's not uncommon, because the end of the barrel is banged or bounced during packaging or shipping or unpackaging or placing/removing from the display rack, for the slightest of damage to happen to the crown. If there is a tiny burr or scratch that can impede the bullet on it's rotation out the bore, it will affect it's flight and by way, it's accuracy.

What is done is the barrel is usually pulled from the action, trued up in the lathe and an angled cut is taken from the very end of the barrel. back enough to eliminate the existing factory crown and making a more sharp, crisp and pronounced end of the threads.

JD
I see... and does this visually impact the appearance of the rifle barrel?

Also, can this be done by a local gunsmith, or is it something that the barrel is generally sent out for?
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Old 04-16-2010, 07:19 PM   #17
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Okay, these examples are REALLY pronounced. Normally the start picture is not this tragic and the finish is not this crazy, but it gives you an idea.

Usually any good gunsmith with a lathe and basic know how can do this procedure. It's usually recommended to get the barrel re-blued as part of the operation.

barrel1.jpg   sdc10403.jpg  
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Old 04-16-2010, 10:40 PM   #18
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Okay, these examples are REALLY pronounced. Normally the start picture is not this tragic and the finish is not this crazy, but it gives you an idea.

Usually any good gunsmith with a lathe and basic know how can do this procedure. It's usually recommended to get the barrel re-blued as part of the operation.
Excellent answers. Very helpful. Thank you much. Given my new rifle appears to be 100% undamaged, this is something that could be waited upon until if/when it becomes visually damaged?? Or would you recommend it anyhow. What is the average cost of this work??
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Old 04-16-2010, 10:43 PM   #19
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Excellent answers. Very helpful. Thank you much. Given my new rifle appears to be 100% undamaged, this is something that could be waited upon until if/when it becomes visually damaged?? Or would you recommend it anyhow. What is the average cost of this work??
On a brand new rifle, unless it was used as a walking cane, it's generally not needed.

It's easy to check if you need it done, just take a cotton ball and run it LIGHTLY around the crown of the barrel. If it does not snag, you are good to go.

As I outlined above, there are other steps that would be money better spent on your rifle.

As for average price on a recrown? $125-$200 depending on the shop.
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Old 04-29-2010, 05:43 AM   #20
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Since 1972, I would not even test fire a rifle without first glass bedding it. Usually, I prefer to float the barrel all the way but some rifles might benefit from a pressure point.
Lapping of the locking lugs and seats can improve contact but it is important to be sure it is necessary and to lap correctly. Locking lug contact marks can be deceptive. Most rifles will, by the wear pattern on the lugs, indicate that the lower lug is contacting more than the top. Indeed, the top lug may show very little sign of contact at all. There is a reason for this.
When the bolt is in battery and the rifle is cocked, contact between the sear and cocking piece lifts the rear of the bolt up until it contacts the top of the receiver bridge. Keep in mind, there is usually a difference in size between the bolt and the bore of the action of from .006 to .011 inch. With the rear of the bolt lifted up, the top lug does not contact. Since most rifles are cycled more empty than loaded, the wear pattern is established and the owner assumes lapping is required.
When a bolt is being lapped, one should not allow the striker spring to provide rearward pressure on the bolt for the reason described. When cocked, the bolt is held in an attitude of misalignment. Ideally, the barrel should be removed from the action and rearward pressure on the bolt should be provided by means of a nylon stub in a threaded fixture which replaces the barrel for the purpose. Spring loaded fixtures are less desirable since a spring loaded fixture will perpetuate a flaw or even make it worse. I have seen fine pre-64 Model 70 actions all but ruined by improper lapping using a spring loaded fixture.
If the bolt is fitting perfectly in the receiver and the lugs contacting properly, this happy state of affairs can be derailed if the bedding is poor. If the bedding surface is uneven, the receiver may be warped when the guard screws are tightend up and the lugs will no longer contact evenly.
The point I am trying to make here is that there is more to lug lapping than meets the eye. In addition, doing it properly requires tools and techniques not available to most hobbyists. Another point is that it is necessary less often than many would have you think.
Recrowning, done correctly, ensures the muzzle of the rifle is perpendicular to the centerline of the bore. Whether the edge is rounded, flat or angled is immaterial provided it is even and true. Of course, a certain amount of recess protects the crown from damage in the field. Again, it is important to stress the words,"done correctly". A crown which is re-cut poorly is no better than the crown it replaces and may be worse. GD

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