First off, I'm not the hot rodder type when it comes to handloads. I don't put velocity over usefulness.

My question comes from the SAMMI preasure limits for the 223 Rem compared to the other 22 centerfires. Is the 223 rem capable of being shot at preasures equal to other rounds like the 22-250 fired in the same actions. The same comparrison when loading the 30-06 compared to a 270 win. or like loading the 6.5 swede in a modern rifle.

I don't know, be interesting to see some replies.
But why do you want to know? I haven't the faintest idea what pressures I have in any rifle.
And there has been many an arguement on AR on how to find out. . . more or less, and maybe this and maybe that.
I don't think the .223 has the same reason to limit pressure as some old cart./rifle combinations, but maybe the brass is made just good enough to hold sammi pressures.
Then there is the mil.ammo thing to watch.

I don't even use chrono's. I just check a few reloading books, work up slowly, and (so far) cases and primers tell me when to stop or go back a bit, to the best accuracy.

I was wondering because my load for h335 shots best at what is suposed to be max, but running at max makes me nervious sometimes. The reason behind the question is that if the 22-250 is safe at 62,000 psi in the same rifle should I be on edge about running a load in the 223 rem at 55,000 psi.

The max pressure is based on the weakest link in the system. That is the cartridge brass.

muck

You've asked a very good question....why can't we load the 223 to 62,000 PSI like we do the 22-250?
Answer:.....BEATS THE CRAP OUT OF ME.....but I've tried and always start piercing primers just a bit over max loads. The 223 case just don't seem to take it like the bigger cases.

I wouldn't be concerned with max loads however....just work up looking for signs as always!

It's not a problem with the barrel or breech not being able to take the pressure but, in my experience, pierced primers that limit pressure in the 223 Rem.

Yep, I've been well up into cratered primers, but the big downside was primer pockets getting loose too quick. Shame to ruin good brass.

If you want to run faster than max loads, buy a bigger gun!!! In most rifles max loads are safe. I had a Remington 700 in 7mm-08 that max loads were too hot. Follow the directions in the loading manual and you should be ok.

Aaron

Aaron, just so, but just a tad simplistic.
IE without looking back, and I hope I'm on the right thread, if the original poster did by a "bigger gun", and used factory loads, chances he would THEN be running at a higher pressure.
Some new loads make your eyes water.

And, just what exactly is a "max.load".
Apparently the max load in your 7-08 was actually over max. So who's max load was it?

Same with manuals. They have to be taken with a grain (pun) of caution for various reasons.

Anyway I dislike the term Max. some people state/boast they are loading X- number of grains over max. Again, who's max.

I prefer the term "comfortable" . It's my max, but not totaly max, and not totaly wimpy, or I might as well buy a smaller gun.

But as for primers piercing due pressure, I've never found that. I've had quite a few, flat, no fireing pin indent and cratered into the fireing pin hole.

A friend was getting Fed. primers piercing with normal loads. A gunsmith said he'd fix that with a heavier fireing pin spring, and he said the fireing pin was too short.

Well that didn't fix anything so he then bushed the bolt face and (something to the pin to fit better I guess), but that fixed it. But had nothing to do with a heavy load.

I have the "Bigger Gun" a 22-250 and 220 swift. I have one load for the 223 though that uses H335 and gives the best accuracy towards hodgdons max recomended charge. The question only evolved from seeing that it was lower preasure (psi) than my other rounds.

Can't tell you about pressure numbers on the 223.. but if one wants max velocity and still have no pressure problems....

I have never had a problem with putting 30 grains of W 748 or BLC 2 in a 223 case with any bullet weight from 60 grains on down....

And I have chronographed some pretty fast velocities in the process...

I have never used the AA powders for the 223, based on lack of availability around here...but on their load data, they rack up some impressive numbers also.....

I just use what works.....

One reason is that you can't run pressure as high in the AR/M16 platform as in a bolt rifle.

quote:

Originally posted by seafire/B17G:
I have never had a problem with putting 30 grains of W 748 or BLC 2 in a 223 case with any bullet weight from 60 grains on down....

I had to back down to 27.5 grains of BL(C)-2 and 50 grain TNT as 28.5 grains was piercing plimers and the bits of metal was creating trouble in the bolts.

You're having better experience than I.

27.5 Grains of BL(C)-2 is a very good load for me!

The CIP (ie. European) standard is 62 ksi, probably because, apparently, they compute piezo psi ratings from crusher CUP ratings using a simple formula. SAAMI does not use such a formula. The CUP ratings are nearly the same at SAAMI and CIP.

I had a Rem. 700 PSS and chambered for .223 AI.

So I was working up loads trying to get a 40 gr. bullet to 3,000 fps. Started getting "flow" around the primer. That seems to be where the pressure signs first appear on this caliber.

Yeah, I was walking way past the listed load specs in the books. Using a chrono and checking brass, all the other signs for pressure.

SAMMI spec is well inside any danger margin, like probably I'm guessing here in the realm of 20% the working pressure that would cause a "catastrophic failure."

First you'll get primer flow; the cup starts to flow around the firing pin. You'll see machine marks on the base of the brass from the bolt face.

Then you'll get "heavy bolt lift" -- The brass tightens up in the chamber and it's difficult to open the bolt. But you should have been tipped off by the primers in the first place.

Heavy bolt lift is getting a bit late in the game.

I'm not up to speed on the 22/250 or 22 Swift. Bigger cases pushing more gas faster down a small bore. I wonder about the dimensions in the web.

If you're shooting published loads -- out of a mfg. load manual NOT off some online wildcat site. If you're using published data, you should be well inside the SAMMI spec.

The only way this all goes south on you is when you're missing a vital step -- like seating the bullet hard into the lands, brass where the primer pocket is shot out, stretched out necks -- so that seating a bullet to the cannalure means it's sitting in the lands.

But if you're following the standard procedures, a max load should not be anywhere near "on the edge."

If you have been around guns for a while, you get more conservative over time because the number of guns that get blown up.

Many companies use the same actions for various cartridges that vary in pressure. The actions themselves are capable of handling higher pressures than most cartridges are loaded to. That does not mean that it is safe to load cartridges to higher pressures. When you get to the pressures between max (reloading book max as you can't choose the pressures you buy your factory ammo at, and if your gun produces pressures that are expected in the book) and blowing the gun up, the brass/primer is the weak link. The brass varying can cause changes in pressures.

Without a calibrated strain gauge on a test barrel, it is impossible to know the pressures you are running at. You can approximate by using a strain gauge and using factory ammo as a baseline, but most people won't even get to this point. Instead they use the descriptions in reloading manuals. Not the safest way to try to gain the last 50 fps.

Aaron

Remember AssClown?
https://forums.accuratereloading.com/eve/forums/a/tp.../331108533#331108533
He disappeared from AR in Sept 2005, but not before divulging some info previously not available to the gun culture.
With Von Misses calculations, he determined that for 806 Tempered C26000 cartridge brass:
1) A Mauser case head [1892 7.65Mauser & 7x57 begat 22-250] would fail at 76,577 psi internal pressure, ~65ksi to the brass.
2) A .223 case head would fail at 86,427 psi internal chamber pressure, ~ 65 ksi to the brass.

With ~18 gr Blue Dot in a .223 with 33 gr Vmax
4,097 fps no extractor groove growth
4,127 fps .005" extractor groove growth

I can higher velocities than that with H110, but my chrono can not measure them.

tnekkcc,

I wish you all the best. Maybe I am just getting old (perish the thought) but more likely having a gun blow in my hand (Glock with factory remanufactured jacketed ammo) has instilled a new attitude in me.

Aaron

Not ammo from Black Hills?
(Re. Gunsmith forum, post by Seafire about a replacement offer by Ruger.)

Not Black Hills ammo.

Aaron

quote:

Originally posted by AaroninUtah:
tnekkcc,

I wish you all the best. Maybe I am just getting old (perish the thought) but more likely having a gun blow in my hand (Glock with factory remanufactured jacketed ammo) has instilled a new attitude in me.

Aaron

Working up a .223 load until primer pockets get loose is a fairly safe excercise, that I would let my kids do.

The safety margin in Glocks is a multi varibale problem.
The gun writer who termed the prase, "kaboom", quotes me on his website on one aspect of qauntifying Glock safety margin.
I would not hand my kids a stock Glock and tell them to work up loads and see what happens.