Are 1/2x28 threads dangerous on 30-06?

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Hannibalbarca
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Are 1/2x28 threads dangerous on 30-06?

Post by Hannibalbarca »

I have the opportunity to purchase a Remington 7600 with a threaded barrel. Over all the deal is very good but the the threads on the barrel are said to be 1/2x28. Is this dangerous to use with a direct thread suppressor? I'll be shooting some pretty hot loads through the gun(buffalo bore supercharged 180 grain).
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doubloon
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Re: Are 1/2x28 threads dangerous on 30-06?

Post by doubloon »

no
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Hannibalbarca
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Re: Are 1/2x28 threads dangerous on 30-06?

Post by Hannibalbarca »

doubloon wrote:no
Really? No deformations or explosions or anything like that? I've always thought that 1/2 made the walls too thin for a high powered rifle cartridge. I'm also concerned about POI shift. I have no technical knowledge of this and I'd like make an informe decision first before purchasing the rifle.
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John A.
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Re: Are 1/2x28 threads dangerous on 30-06?

Post by John A. »

5/8-24 would be more ideal for 30-06.

Cutting and threading a barrel shouldn't be a deal breaker if that is your only concern.

I had a Remington 7400 in 06 for a while.

Good gun.

For the first 3 shots, after that and I would get a lot of vertical stringing.

And it rusted if you looked at it wrong.
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Hannibalbarca
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Re: Are 1/2x28 threads dangerous on 30-06?

Post by Hannibalbarca »

John A. wrote:5/8-24 would be more ideal for 30-06.

Cutting and threading a barrel shouldn't be a deal breaker if that is your only concern.

I had a Remington 7400 in 06 for a while.

Good gun.

For the first 3 shots, after that and I would get a lot of vertical stringing.

And it rusted if you looked at it wrong.
Any reason for the vertical shift? Also I should say that the suppressor I'd be using would be a really heavy all stainless steel one, definitely more than 30 oz. I'd have a POI shift but I'm just concerned with the smaller thread size having it be exacerbated. Yeah I really wish they had made them in stainless steel. It's the only 30-06 rifle with a detachable magazine for a fairly low price that I could find, barrel is also threaded which is nice. I always spray down the bore of all my guns with an anti corrosion spray and do the same with the rest of the gun so I'm not too worried about rust. Do you know what the barrel diameter is on them? It might be less than .625 at the muzzle so 5/8x24 wouldn't be possible.
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Re: Are 1/2x28 threads dangerous on 30-06?

Post by BobbyJohn »

With the thinner barrels, like you have, I have seen a couple of baffle strikes destroy the end of the barrel, so you have to make sure everything in lined up almost perfectly, I also suggest, shooting the particular ammo you intend to use with the suppressor without the suppressor to see how they pattern. That said, as long as everything is aligned correctly, you should not have any problems.
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Hannibalbarca
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Re: Are 1/2x28 threads dangerous on 30-06?

Post by Hannibalbarca »

BobbyJohn wrote:With the thinner barrels, like you have, I have seen a couple of baffle strikes destroy the end of the barrel, so you have to make sure everything in lined up almost perfectly, I also suggest, shooting the particular ammo you intend to use with the suppressor without the suppressor to see how they pattern. That said, as long as everything is aligned correctly, you should not have any problems.
Do you think with the thinner thread pitch that I'll see a lot of POI shift with everything else being equal vs if it was 5/8?
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Re: Are 1/2x28 threads dangerous on 30-06?

Post by BobbyJohn »

Hannibalbarca wrote:
BobbyJohn wrote:With the thinner barrels, like you have, I have seen a couple of baffle strikes destroy the end of the barrel, so you have to make sure everything in lined up almost perfectly, I also suggest, shooting the particular ammo you intend to use with the suppressor without the suppressor to see how they pattern. That said, as long as everything is aligned correctly, you should not have any problems.
Do you think with the thinner thread pitch that I'll see a lot of POI shift with everything else being equal vs if it was 5/8?
I don't know if others find it true, but my partner and I who also make suppressors, have found that the POI on the thinner barrels has to do with the harmonic vibrations that affect the thinner barrels more than the heavier barrels. I don't know how much POI shift you will see in your situation, but based on what you said about shooting hot loads, I would suspect you will see more with the thinner barrel than you would with a heavier barrel.
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John A.
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Re: Are 1/2x28 threads dangerous on 30-06?

Post by John A. »

Hannibalbarca wrote: Any reason for the vertical shift?
Dang if I know, but that gun was always ate up with it. I always attributed it with the barrel heating up.

Bought new, sold it later and have not missed it.
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joaquin
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Re: Are 1/2x28 threads dangerous on 30-06?

Post by joaquin »

I had some sporter barrels threaded last year. I had Class 3 Machining do the work. They recommended 9/16 due to the profile. 5/8 wouldn't work due to the contour, and they felt 1/2 was too small to be safe.

I was able to purchase an adapter from Brownell's for like $30 that is basically a bushing to go from 9/16 to 5/8. It was designed for suppressors, so it's not just a run of the mill bushing that you could purchase at a hardware store.

Also, Class 3 charges like $50 for threading, so you could purchase the rifle and send it in and have it shortened and rethreaded for a reasonable amount.
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Re: Are 1/2x28 threads dangerous on 30-06?

Post by cliffy109 »

I've got a custom scout rifle built on a Mossberg Patriot Youth in .308. The barrel was cut to 16.5" and the builder threaded it. He couldn't do anything other than 1/2x28 so that's what I have. I have been shooting a direct thread Silencerco Harvester with no problems. I did try a few groups at 100 with and without the suppressor and the groups with the can were less than 1" higher than without. I attributed that to perhaps slightly increased muzzle velocity and didn't worry about it.
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Re: Are 1/2x28 threads dangerous on 30-06?

Post by ECCO Machine »

I put 1/2-28 on .30 cal sporters all the time, including various 300 magnums. Very few "hunting" rifles have thick enough barrels for 5/8-24 at full length, and will usually still need a collar if shortened 3 or 4 inches. Don't generally do 9/16 threads because it severely limits muzzle brake and direct thread mount options without adapters.

The two major considerations for necessary wall thickness are temperature and pressure. As hunting rifles tend to retain longer barrels for ballistic reasons, the exit pressures are lower. Said rifles also don't tend to be rapid fired, so it's extremely unlikely that it'll ever even get uncomfortable to hold at the muzzle end, let alone reach temperatures which affect the steel's mechanical strength. Ergo, there's no problem with 1/2-28 threads on a .30 cal sporter.
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