I know I'm taking a chance, but I have shot about 1000+ rounds of LC and IMI M193 through a Krieger .223 REM chambered barrel.  

It was one of there 4145 chrome moly 1-9 barrels and I like that I could typically/consistantly get under an 1.5"  (5-shot) and no KB.  

I know to look for overpressures signs, but none to date.  

Now I want to try one of Kriegers SS 1-9 or slower twist for the same ammo/chamber.  Do you think there may be a difference in that CM being stronger may handle the higher pressure better than a their SS offering?  My goal is to squeeze the most accuracy out of those crappy M193 bullets.

I have a friend that has a Savage 223rem he bought it in 86
Anyway he allways shot the  PMC M193/Q3131 etc!

Never any signs of pressure

My Savage is in 222rem

I would get pissed when he would pay 2 bucks a box
I would have to pay 9 bucks for 222rem

Its your face, do what you want.

There is a reason there are two different chambers available.  You may never have an issue, but......

edited ––––- had my facts backwards  ––-   that Savage bolt rifle in the post above has a nice thick ring of steel surrounding the bolt,  not aluminum like an AR-15.    If the gentleman was over -pressuring it then,  he may never have noticed  and it may not have hurt the bolt rifle one bit,   ––––- an aR is a little different animal though ––

(you can see my original response in RFUTCH's quote below if you need a laugh ––- sometimes beer and the internet dont mix)

This is from TOS

"Here's a very interesting quote posted by Ned Christiansen


". . . In short, you can safely fire all 5.56 AND 223 ammunition in a gun properly chambered for 5.56. You MUST NOT fire 5.56 ammunition in a 223 rifle. As case in point, I fired XM193 5.56 ammunition in a 223 test barrel with average pressures (conformal transducer) of 72,550 psi, and peak pressure registered at 76,250 psi. . ."

Since the SAAMI MAP for the .223 Remington is 55,000 PSI, that puts XM193 fired from a minimum spec .223 Remington chamber at 17,550 PSI over the maximum. "

This is not sound advice.

This is.

RFUTCH is right –– don't do it  -  (i had my info backwards )    5.56 in a 5,56 chamber is not much higher than .223 in pressure  (55k vs 58k)  –– but loading them in the tighter .223 chamber spikes it another 20k.   This obviously hasn't grenaded your rifle yet and probably won't ,  but then again.  Its a steel bolt housed inside aluminum.   Its not going to hold together like a quality bolt rifle.     Putting a .223 in a 5,56 will give you no issues though

On the bright side, if you save your brass for reloading , all your brass you've already fired is now , in effect .223 brass.

If you've got a ton of 193 to shoot up,  maybe look into a 5.56 barrel for a few coins on the EE

or you could get the reamer from Ned Christiansen and make your 223 into a 556 chamber...if you were inclined that way and had the skills to do it.

Mark

You were probably thinking about .308 vs 762. In this case .308 is the higher pressure one

A controlled explosion 6 inches from my face is not something I would take any extra risks with.

Accuracy is found first in the quality of bullet you use. FMJ's are notoriously poor performers. The only one on the market that's worth trying is Hornady's 55 grain fmj and their 55 grain SP. All other's are crap. Krieger can not make up for it once it leaves the barrel.

If you are willing to pay for a Krieger barrel you should be willing to buy better bullets. Since Ned Christensen has already been mentioned, probably the premier 1911 builder in the nation, he also sells a reamer that will throat your .223 chamber to 5.56mm thereby eliminating any pressure problems. This can be done (carefully) by you at home.

You could also remove the barrel and send it to any number of gunsmiths who would be happy to touch a 5.56mm chamber reamer to the .223 chamber you already have. This service probably would be cheaper than actually buying Ned's reamer, however Ned's reamer will be yours to keep.

I haven't a clue why Krieger is still selling their "in house" pre-made barrels with a .223 chamber, but they do. Nobody in highpower competion wants a .223 chamber, they want a "Wylde chamber", a "CLE chamber": or a "5.56mm match" chamber. The .223 throat is just too short for the bullets we use. Instead of buying a barrel direct from Krieger have John Holliger or Frank White turn a 1/7 or 1/7.7 or 1/8 twist Krieger barrel blank to your specs. You will get a barrel that allows you to shoot the cheap ammo that way, but has the potential of being a real tack driver when it comes to the good stuff.

Forget the fmj's if you are serious about accuracy, they don't work.

+1

I run M193 through my Rem. 788 all the time.

Ironically......



During the great ammunition panic of 2009, I bought a 100 round box of the Federal 223 value pack ammo at Wal-mart.  Upon opening the outer box, there were (5) 20 round boxes inside labelled XM193.



I didn't care...I'm all chambered for 5.56.

Your experience is like FMJ's experience with his Savage mentioned above .      An AR bolt carrier group is steel, but housed inside an aluminum receiver (which if something ever let go would be pretty spectacular).   A Rem 788 on the other hand has a thick tubular steel receiver surrounding a bolt with 9 !? locking lugs.   A Weatherby Mark 5 action also has 9 locking lugs and is considered one of the strongest out there.    An AR upper receiver is not as bomb proof as your receiver is

Anyway –––– you'd probably have to load your cases with pistol powder or something to have a serious problem ––- a mere 20k pressure spike likely won't do anything in your rifle  (and obviously hasn't yet).   Sometimes when you overpressure it, you will notice sticky extraction and funny looking primers (primer flattens or elongates more than usual) –– sometimes you dont notice anything.

Not a good idea.

Main reason Robert bought M193 for his savage  was because of lack of money back then.
Poor country boys

That rifle has shot buckets full of m193 spec ammo


Yeah I dont see a modern 223rem BA KABOOM by shooting 1rd of  mil spec M193
I bet there proof loads have even more pressure

I'd be more worried about my barrel life.

The American eagle 100rd packs we've been seeing at gander are marked and sold as 223 but the ammo sure seems like the same xm193 that federal has been selling for years...

What about the .223 wylde chamber? You can shoot 5.56 out of it right?

Im pretty sure, I think wylde and 5.56 match are the same, or VERY close, its in between a 5.56 and .223, loose enough to take 5.56 with no problems, but tight enough to shoot very nice groups with .223 or 5.56.  Best all around chamber out there.

Yes you can.

But the aluminum has nothing to do with it. The part where it counts is in the lugs of the bolt and the barrel extension. You are correct about the 788 having over kill with the "I think it is eight" lugs especially with a .223 round. I may have a well worn leade/throat that lets me do this.

I dont know but I have never seen a SAMMI AR in my "real" life to say. At a range not a gun show.

You're lucky as a rule of thumb mechanical engineers design to 150% of threshold.

Use the correct ammo for the specific chamber. Just because folks have been getting away with shooting 5.56 in a .223 chamber doesn't mean it's a wise decision.

He still has the savage rifle
He bought it used in 1986