My next project will be an 18-22" suppressed .223 bolt gun.  Trying to decide on twist rate, 1-7 to 1-9", and what chamber reamer to use.  I do reload, but I'd like to be able to shoot M193 at close range for cheaper plinking on steel out to 300, and I have a fair amount of IMI 77 grain ammo for out to maybe 600.  

Those that have built .223/5.56 bolt rifles, what worked, what would you change/suggest as far as chambering reamer and twist rate?  Main uses would be prone on steel, maybe some coyote hunting.  

Base action is an old LH 700.  I already have a 26" heavy .22-250 and a heavy .308 bolt action.  



Thanks.

1/8 will stabilize everything to 80 grains, 1/7 will too.  

I'm doing a 1/8 .223 Wylde Remington 700.

My .22-250 has a 1-9 as it is a coyote/crow/woodchuck rifle and I mainly wanted to shoot 55-60 grain varmint bullets and I was afraid a 1-7 might be too fast.  I think I'll go with what you suggest, 1-7.7/Wylde.  

What COAL are you loading to with the 75's?

My factory barreled Savage with 1/9t does great with 75g Amax loaded at 2.5 using MDT mags.  When I eventually replace the barrel it will be 1/7 or 1/8.

Barrel length has a lot to do with it.  My 26" 1/9" does ok with 77gr SMKs on a hot day.  I haven't tried 'em in the cold.  A 16 or an 18" 1/9 would not do nearly as well with the lower velocity.

If I was going shorter than 20", I'd go 1/7.

I have a couple of custom 223's. One has a 1-7 the other 1-8 twist. A disclaimer, they both shoot very well. Having said that I dont think in most cases you have to go 1-7. So far the 1-8 has worked great with everything I have tried (including 80gr bergers).  I use mostly match bullets (69 and 77gr), but if I was using bulk 55gr ammo, I think I would lean toward the 1-8 twist. My suggestion would be to bounce this question off the the barrel maker you intend to use. Once you tell them what bullets you want to use, they can steer you in the right direction.

I have a Sako Varmint Stainless with a 1/10 twist which shoots the 55gr Hornaday V-Max into one hole at 100yds. mostly for ground hogs.

Do you want the full BC of the 75amax in some conditions or all conditions OP?

If the answer is all conditions, then get a 7 twist.
Just because you get good groups doesn't mean your bullet is 100% stable, any pitch and yaw due to instability reduces the BC of your bullet.






Run your numbers here OP.

http://www.bergerbullets.com/twist-rate-calculator/

My 4000 ft elevation helps too.

I bought a little Ruger American  Ranch since Remington still does 1/9.
  This is just a little fun suppressor host but with 1/8 I can shoot the 75 Hornady or the light weight stuff if I wanted.
        I for one like they used the 5.56 chamber even though I'd prefer the wylde.
  I'm sure if marketing wasn't a consideration they might of. If I had your base rifle I'd do the McGowan "remage" in .223 wylde 1/8 twist 18in length .

Thanks everyone.  I was up in trees relaxing the past couple days and managed to start filling the freezer back up.  I have a no gadget policy when hunting.  

Sierra suggests a minimum of a 1-8 twist for the tipped 77/80 SMK's, that would be the heaviest bullet class I intend to use, mainly it would be M193, which would get me fire formed brass, and either 69/77 grain SMK's, whatever ends up shooting better.  

I'll probably go with Wylde/1-7.7.   Worst case scenario, it does not like 77's, and I use up some 15 year old bulk packs of 69's.  


I went with 1-9 with the .22-250 as I was afraid lighter varmint bullets would not like too fast of a twist, maybe the next barrel with be an Ackley Imp., and 1-8.  There was an article many years ago called "Half Mile .22's" by Ross Seyfried that was interesting.  Fast twist, heavy bullets (greater than 69 grain) seated long.   Anyone play around in this area?  There was an article in Precision Shooting years ago by one of the tech head writers there that warned of pressure problems when shooting bullets with a long bearing surface in fast twist barrels backed by lots of powder.  I think it was mainly with the smaller bores.  

I bought a 700adl during the black friday deal a while back thinking that I will chop and thread it and maybe re barrel down the road. Probably should have just bought the Ruger Predator at this point as it was almost exactly what I wanted to end up with and has the proper twist.

Eventually a custom built one will probably be in the cards. Have talked to a few people with 223AI bolt guns that like them very much.


Why not shoot the 80's? Are the 75's better?

I remember reading a article with a guy shooting a fast twist 22-250 out to 1000. Pretty interesting but it was a long time ago. I could be wrong but I think barrel/throat life wasn't great on it either.

I'm kind of on the same boat...  I want to build a Rem 700 in .223 and have a lot of questions.  I want to shoot either BH MK262 OTM or another cost efficient clone...  IMI or CBC...  I plan to go with a Hart barrel, in either 1/7 or 1/7.7.  Its going to have an 18.5" barrel sitting in a MCM A1-3.  Kind of like a Mini-Me of the Darpa XM-3.  Should I go with a 5.56 chamber or a Wilde .223?   Eventually I want to reload for that rifle, but hell, I've only just bought me the suppressor for the rig.  Still have a long way to go.

That's the same thing I'm doing.  I have a considerable stash of MK262 and burning it all through an AR gets old.  

I'm doing a 26" 1/8" 5-groove Pac-Nor.   I wouldn't put that ammo through a real good barrel.  I had settled on a Wylde chamber, but I think I'm going to send the 'smith a few rounds of what I have and tell him to cut the best chamber for it as I have enough to completely burn that barrel out.

I bought a 26" 1/8 to replace my 26" 1/9 Winchester factory barrel. I haven't decided on the chamber yet, a CLE or Wylde are top contenders.

Samuse and you other guys.....  How does one know that it is acceptable to ream a chamber for the higher pressure of 5.56?  I am really wanting a .223/5.56 bolt gun too and am getting ready to see if I can take one in on a trade.  But my mind always stops with the, is it OK to modify the chamber, question.   I figure if I try to trade for one I'm more likely to get something used that doesn't have a 5.56 chamber.  Because it seems like that is more of a newer thing among manufactures.  

Like the Remingtons, I've been eyeing a .223 bolt gun for over a decade and the LTR, I believe, was just .223 and not 5.56.  At least it was never listed as a 5.56 chamber in any of their brochures or websites.  And I don't think they show it (any of their .223 bolt guns) as 5.56 now.  So how do you know it's OK or acceptable or not above the parameters / safety of the action to shoot the higher pressure?  

There are also some actions that are designed around the .223 that make that even more questionable.  Obviously with the 700 action or a say a Model 10 savage, that are also chambered in other higher pressure rounds, like .243 or .22-250, then you could see how it would handle 5.56.  But like CZ has that little bolt gun in .223, that also comes in 7.62x39.  Or the Savage 25.  Those appear to be designed around the intermediate rounds and the extra pressure of the 5.56 may be too much?  

Have you guys called manufactures, or are you getting advice from custom makers or what?  

I've been wanting to do this for years and years but have never quite done it because of money and this big question mark.  But I'm getting to the point that I'm not sure if I'm going to fight it any longer.  


Also OP, your question about long range with the .223....  When I first started shooting I joined this association.  I think it was called the Varmint Hunters of America.  Or VHA for short.  They had a quarterly magazine.  I think it was.  Or maybe it was monthly.  And it was a bunch of dudes that mostly shot Prairie Dogs and the like and they were constantly talking about rigs that could shoot the varmint type rounds a long way.  .243 was considered large in that community but some used it.  Lots of .22-250 talk and such.  Wildcat calibers.  You may want to look into it and see if it's still around because those guys knew a thing or two about putting together long range rigs for prairie dog shooting.  They'd show different members getting hits on prairie dogs at extremely long ranges.

From what I've been told by a few good 'smiths is that the throat on a factory Remington .223 is so long that it'll shoot any 5.56 without problems.

My 700P in .223 will shoot MK262 just fine.  I had the 'smith check it against a .223 Wylde reamer but I don't think he had to do anything to it.

My cousin once told me he was shooting M193 in his Dad's Ruger .223, which was a long time ago.  Before they would've chambered it for 5.56, I'm guessing.

But it seems to me there is two points about over pressure in this case to be concerned about. The first, I guess would be if the chamber is too tight for a 5.56 round, that will just create MORE pressure than what should be there.   Correct?  But the second issue I'm more talking about is if a particular action has been designed to take the higher pressure of the 5.56 over a .223 round in a chamber that was designed for 5.56.  I know it's not a lot, and it seems like the consensus is, nobody cares.  But is there basically anybody knowledgeable that has told you that certain particular actions are designed for it or not?  

I'm probably overthinking it but it seems like an area to sort of be anal about.  Maybe not.   It reminds me of the stories about when they started loading .44 specials hotter in the making of .44 mag.  Some guns obviously broke from the extra pressure and probably recoil.  I think that was probably a more drastic jump, but maybe you get what I mean.

In both of my Remington 223 rifles, a VS and an SPS, I have shot 5.56 ammo with the only sign of pressure being a slight amount of primer flow.  Some of my reloads have showed similar results.

As far as twist rate goes, I can tell you that the 75 Amax and the 53 Vmax shoot very well out of my 22" 1:7.5 twist Krieger 223AI at altitudes from 500 to over 5000 feet.  Velocity is faster than standard 223 but not by enough to make a difference.

My current project is a 223 Remage Wilson 22" in 1:7 twist and I am hoping it will stabilize the same range of bullets.  I should know by the end of the month

Could we get some of you guys with .223 bolt guns to post pics of yours in here????

You know, I've always had those concerns about a factory Rem 700 in .223, can they handle the 5.56...  Well good to know, nonetheless, I want to feed it 75-77 gr projectiles, so I will just rebarrel the gun.  If I'm building the gun from scratch, might as well go with a Shilen, Bartlein, or Hart barrel.  I guess who ever I get the best price from.  I imagine that any one of those mfr's can provide a more that adequate accuracy for my intended purposes.  I really wanted a .308 gun, but I just can't justify when I'll probably never shoot past 600.  I figure I can have a lot more fun with the 5.56/.223.

I don't think barrel length has as much to do with it as you think. I have a 26" Savage 9 twist 223 and when I measured it 4X I came up with 8 5/8" twist. Loves 75gr Amax. I'm going to measure my Ruger Hawkeye one of these days. I use the Ruger for deer and TSXs.

Do you put 5.56 through yours at all?

Varmint Hunter (VHA) has been closed for several years, as has Precision Shooting.  I subscribed to both for many years, I could probably insulate a small building with old issues.  

Yes. Linda Lovelace throats from the factory in my Savages. The Ruger I have put 5.56 through it but I've only done it once for sight in purposes. No issues.

They're defunct eh?  Oh well.  

This ! 1:7

Me too.  26" 3-groove SS #7 Lilja, fluted, threaded and Cerakoted.

You must be over 70.

No slower than 1:8 with 1:7 having a few more bullet options (90s for example).

Also not that caliber per caliber basis:: 1:10 in 0.308 is equivalent to 1:7.2 in 0.224.

Here's one of mine.



Started as a Remington 700 AAC in 300 Blackout
Broughton 5c w/ a Wylde chamber, varmint contour, 1:7 twist, 16.5" long and profiled for a Surefire FA556MB.
Mcmillian A5 in desert spectre, inlet for badger metal.
Nightforce 3.5-15x50

I shoot M193, M855, Mk262 and anything else I have handy, I have not seen any signs of pressure issues with anything I've shot. I rarely shoot for groups, but I get consistent hits out to 800 yards on 2/3rds idpa steel with most match factory and heavy hand loads.

That is freaking awesome.  Thanks for the input on 5.56 pressure.  I so want a bolt gun.   Nice glass on that thing too.  Well the whole thing is really nice.