I have a 24" fluted bull barrel for my AR Grendel that i would like a brake or flashhider on but the flutes end 3/8" from the end. Is that going to be enough threads? I really don't want to get into the flutes if I don't have to.
Gunsmithing How much thread do you need?
- Thread starter Milan metal
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Re: How much thread do you need?
I'd say 3/8" would be marginal at best. No way would I run a suppessor on so little thread, even a brake or flash hider timed to the shoulder (no crush washer) is iffy, and I wouldn't do that either, just my .02!
I'd say 3/8" would be marginal at best. No way would I run a suppessor on so little thread, even a brake or flash hider timed to the shoulder (no crush washer) is iffy, and I wouldn't do that either, just my .02!
Re: How much thread do you need?
Thanks for your input.
I will not be running a suppressor at anytime so that doesn't worry me.
I just measured it again and it is exactly 7/16". I am not a barrel expert but from what I know about a piece of stainless that is strong enough to hold a 3-4" piece of brake? No? If not how long is the minimum?
Thanks for your input.
I will not be running a suppressor at anytime so that doesn't worry me.
I just measured it again and it is exactly 7/16". I am not a barrel expert but from what I know about a piece of stainless that is strong enough to hold a 3-4" piece of brake? No? If not how long is the minimum?
Re: How much thread do you need?
In general, I'd like to see flutes terminate at least a full inch from the crown, because it is CRUCIAL the bore is nice and round there. Flutes tend to (slightly) cause the bore to be out of round -even polygonal in shape.
That said, your flutes are already too close, and adding a brake isn't going to make them closer.
With 7/16" to work with, you can manage 1/4" thread, 3/32" thread relief, and 3/32" of shoulder before the flutes begin. No chance of a crush-washer, but it'll be strong enough to do what it needs to do.
Far from ideal, but oughtta work.
In general, I'd like to see flutes terminate at least a full inch from the crown, because it is CRUCIAL the bore is nice and round there. Flutes tend to (slightly) cause the bore to be out of round -even polygonal in shape.
That said, your flutes are already too close, and adding a brake isn't going to make them closer.
With 7/16" to work with, you can manage 1/4" thread, 3/32" thread relief, and 3/32" of shoulder before the flutes begin. No chance of a crush-washer, but it'll be strong enough to do what it needs to do.
Far from ideal, but oughtta work.
Re: How much thread do you need?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">In general, I'd like to see flutes terminate at least a full inch from the crown, because it is CRUCIAL the bore is nice and round there. Flutes tend to (slightly) cause the bore to be out of round -even polygonal in shape.
That said, your flutes are already too close, and adding a brake isn't going to make them closer.
With 7/16" to work with, you can manage 1/4" thread, 3/32" thread relief, and 3/32" of shoulder before the flutes begin. No chance of a crush-washer, but it'll be strong enough to do what it needs to do.
Far from ideal, but oughtta work. </div></div>
+1
Danged ol' flutes
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">In general, I'd like to see flutes terminate at least a full inch from the crown, because it is CRUCIAL the bore is nice and round there. Flutes tend to (slightly) cause the bore to be out of round -even polygonal in shape.
That said, your flutes are already too close, and adding a brake isn't going to make them closer.
With 7/16" to work with, you can manage 1/4" thread, 3/32" thread relief, and 3/32" of shoulder before the flutes begin. No chance of a crush-washer, but it'll be strong enough to do what it needs to do.
Far from ideal, but oughtta work. </div></div>
+1
Danged ol' flutes
Re: How much thread do you need?
So is the one inch for all barrels and calibers? I bought this barrel from one the best Grendel builders in the country (from what everyone on this forum told me).
I think I am going to order another barrel without the flutes anyways so I will just wait for the brake on that one.
Thanks again.
So is the one inch for all barrels and calibers? I bought this barrel from one the best Grendel builders in the country (from what everyone on this forum told me).
I think I am going to order another barrel without the flutes anyways so I will just wait for the brake on that one.
Thanks again.
Re: How much thread do you need?
In most instances, you want a thread length equal to the thread diameter in order to adequately support the mating part. More is always better, but this is a good general rule.
Good luck.
C.
In most instances, you want a thread length equal to the thread diameter in order to adequately support the mating part. More is always better, but this is a good general rule.
Good luck.
C.
