Wanting headspace checked on my AR

[sloughfoot]

Well, now, sloughfoot, you'll get your cases stuck & such. Worse case, you're gonna get broken cases.

Then you're in trouble..

And have to dig them out with your knife? That would be horrible indeed! Especially if Indians are charging up the hill.....

 

[sloughfoot]

Im referring to a situation where too little headspace causes the neck of the casing to be forced into the throat exaggerating the crimp on the bullet. The bullet then starts to behave more like an obstruction than a projectile. COL obviously can play a part in this as well, but there is a generally accepted minimum amount of desired headspace for this reason.

You have successfully confused headspace with a too long case. They are two totally different things. And not related in any way. Unless you are shooting a benchrest rifle, which this discussion is not about. It is a huge chambered AR.

 

[indyjohn]

And have to dig them out with your knife? That would be horrible indeed! Especially if Indians are charging up the hill.....

Gotta be wary of those Indians, they're fast!

Not to diminish the concerns of the OP & the smith. But, dog gone, the odds of there being a problem with a brand name parts build are just really slim.

 

[bulletsmith]

You have successfully confused headspace with a too long case. They are two totally different things

Ok, fair enough. And I'll even concede that what I believe I understand on the topic comes from this site and reading a number of other sources. So educate a little here. What you are saying is contrary to virtually everything I have found on the topic so far. Are you saying that too little headspace does not cause increased pressure?

 

[bulletsmith]

Gotta be wary of those Indians, they're fast!

Not to diminish the concerns of the OP & the smith. But, dog gone, the odds of there being a problem with a brand name parts build are just really slim.

For sure, I just found it odd to say that headspace should be ignored.

 

[indyjohn]

For sure, I just found it odd to say that headspace should be ignored.

Well, I believe with the state of machining technology today it is much more consistent than it once was in the days of our grandfathers. Add to that QC checks, it makes the odds of a bad example getting out so small.

I mix my lots of powders for this reason as well, the technology is advanced to the point of variance between lots is so small that it is only a concern if you load to extremes. Which I don't.

 

[sloughfoot]

Us graybeards laugh at the wisdom on the internet since the experts have been opining on it.

No it does not cause increased or at least, not dangerous pressures.

And 5.56 Mil-spec can safely be fired out of .223 chambered rifles, but 5.56 NATO should not be. It is important to know the difference between the two.

And 9mm bullets can not be pushed far enough into the case to cause dangerous pressures. The powder will only allow the bullet to go back just so far.

And all metal AR's are the same. Only the marketing and pricing distinguish them from one to another.

The pencil barrel Mini14's are combat accurate.

There. I've said it.

 

[sloughfoot]

BTW. I didn't mean to imply that headspace should be ignored. Just that it is not dangerous. It is what you work with when resizing your fired cases. Whatever it is, the shoulder should be set back a maximum of .004 for any rifle. When guys neck size only, they are doing nothing with the shoulder.

Headspace is easily checked using a case gauge.

I am keenly aware of the headspace of each of my rifles.

I own many AR style rifles. They all have identical headspace. INDYJOHN nailed it. There is no variation with modern manufacturing techniques.

 

[bulletsmith]

Us graybeards laugh at the wisdom on the internet since the experts have been opining on it.

No it does not cause increased or at least, not dangerous pressures.

And 5.56 Mil-spec can safely be fired out of .223 chambered rifles, but 5.56 NATO should not be. It is important to know the difference between the two.

And 9mm bullets can not be pushed far enough into the case to cause dangerous pressures. The powder will only allow the bullet to go back just so far.

And all metal AR's are the same. Only the marketing and pricing distinguish them from one to another.

The pencil barrel Mini14's are combat accurate.

There. I've said it.

I don't know what you could to an AR to change Headspace for any reason. I get that. As for the 9mm (and other handgun) I wasn't actually concerned for that very reason. I guess I was mainly thinking of bottle necked rifle rounds. The Mini14 statement is lost on me.

I'll have to seek out more info on the mechanics of pressure as it's influenced by headspace.

Sorry for the hijack OP.

 

[bulletsmith]

BTW. I didn't mean to imply that headspace should be ignored. Just that it is not dangerous. It is what you work with when resizing your fired cases. Whatever it is, the shoulder should be set back a maximum of .004 for any rifle. When guys neck size only, they are doing nothing with the shoulder.

Headspace is easily checked using a case gauge.

I am keenly aware of the headspace of each of my rifles.

I own many AR style rifles. They all have identical headspace. INDYJOHN nailed it. There is no variation with modern manufacturing techniques.

Are you referring to the AR's or bolt guns included?

 

[sloughfoot]

.004 for all rifles. AR's included. Bolt guns included. M1A. PTR 91. AR 10. Remington 700. Winchester 70. Mauser 98.

.004 maximum shoulder set back when reloading. I try for .002 but case springback has an effect. So I go for a little extra.

 

[indyjohn]

-.004 always.



Building LR Palma loads for my M1903 with its new Lyman Peep Sight.
https://www.indianagunowners.com/forums/gunsmithing/394012-whats-best-method-surface-rust.html

 

[bulletsmith]

This is good stuff. I started another thread so we can quit hijacking this one If you guys could head over there I would love to continue this.

https://www.indianagunowners.com/fo...eadspace-neck-sizing-other-internet-lies.html

 

[Dudelittle]

If you a're "building" rifles, hadn't you better order a set of gauges yourself?

(Don't forget to take the ejector out.)

If I build another it will be a long time from now, so long to not warrant buying gauges.

 

[Fargo]

If I build another it will be a long time from now, so long to not warrant buying gauges.

Why don't you call Faxon and ask them if they check headspace on their barrels before they send them out? I have a sneaking suspicion they do...

 

[Dudelittle]

So the bolt plays no part in proper headspace?

 

[natdscott]

The bolt plays HALF the part in correct head space of the rifle platform. By your posts, dude, you are strongly suggesting that you may not have the skills and/or knowledge to be putting your own rifle together. That's not an insult, that's a demonstrated fact. You need a smith, at least for a little while.

What Fargo may be intending to say is that, because milspec bolts vary no more than about 0.001" either way, if the barrel is correct for ANY milspec bolt, it is Fargo (and many other contributor's) opinion* that the barrel is good with ALL milspec bolts.



*Please note that that is not necessarily my opinion, but that I have some more exacting standards in mind for the rifle than most shooters and builders of AR-15s.

-Nate

 

[1911ly]

Wow! This thread is just turning in to a unnecessary pissing match. If the OP feels safer checking the head space "so be it". We all have our opinions. The one that makes the OP sleep better is the one that counts.

We've all offered our opinions. The OP can decide what is useful in this thread. Any more commenting is just a unnecessary and just another pissing match starting.

OP, let us know how your gun shoots.

 

[natdscott]

1911ly, that's pretty disrespectful to some of the people who have spent a little bit of their life trying to help the OP.

The OP, it seems, wishes to find out what is the safest direction for he and his rifle, and I believe some of the rest of us have given that to him. Besides that, he is always free to take whatever direction he chooses, regardless of what you or anybody else says on 'da interwebz', so it is your most recent comment that is unnecessary.




Dude, I'll leave you with this: The internet as a whole does tend to enjoy making rules of thumb such as "AR's don't have to be checked...", however, at the end of the day, the internet is not the one doing the firing of the real rifle. As it is only YOUR face that is behind the rifle you just built, if you want to follow the correct path for the longevity of your face, you should check the rifle with the correct tools.

For anything made of some thin steel and aluminum that is supposed to hold in 50-60,000 PSI...That's a gauge.

I'll make this offer: If you want to order a Forster 5.56mm Go/No-Go set (HG556NATOMin and HG556NATOMax) and sell it to me as a spare, I'll meet you, use them on your rifle, and you can go home with a safe weapon, and most of your money back in your pocket for gauges you don't want to keep.

-Nate

 

[Dudelittle]

Thanks.. I took it out and its fine. Cycles, and its putting casings at about 4-5 o'clock. Only 10 rounds out but it started raining more then I wanted to stand in.