Barrel swap without go, no-go gauges?

[Robinhood]

I can't believe how much misinformation and dangerous suggestions about headspace are on here. For a person that deals in thousands of an inch for a living it is not so scary. For the average person who has never done dimensional measurements.... it can defy logic. Hottolds hit it as did joeb and RC 20. If you shoot factory ammo, gauges are a safe bet. I would be more afraid of head protrusion than missing headspace by a small amount for the reason RC 20 stated. There is a small window that you can set headspace within. If you size your brass excessively small, the face of your bolt head could possibly rub on the face of the barrel breach. If you use brass to headspace and you comprehend the process and understand what the datum is and how it is measured there is a good chance the sky will not fall. If you are unfamiliar, use a gauge.....check it thrice. The most important thing when head spacing a barrel is that you understand all of the relationships that are involved.

[Robinhood]

Read this and you may re-think your position. http://www.sinclairintl.com/GunTech/Headspace-Why-It-s-Important-How-To-Check-It/detail.htm?lid=17125 I did not see anything that harmed anyone. In my younger days with no mentor I did some foolish things as a reloader. Fortunately I survived. I also learned when an Savagesmith goes by internet articles and posts and not real world experience.

[RustyShackle]

For a person that deals in thousands of an inch for a living it is not so scary. For the average person who has never done dimensional measurements.... it can defy logic. Hottolds hit it as did joeb and RC 20. If you shoot factory ammo, gauges are a safe bet. I would be more afraid of head protrusion than missing headspace by a small amount for the reason RC 20 stated. There is a small window that you can set headspace within. If you size your brass excessively small, the face of your bolt head could possibly rub on the face of the barrel breach. If you use brass to headspace and you comprehend the process and understand what the datum is and how it is measured there is a good chance the sky will not fall. If you are unfamiliar, use a gauge.....check it thrice. The most important thing when head spacing a barrel is that you understand all of the relationships that are involved.

I think the biggest issue is encouraging individuals who have little to no idea what a "thousands" of an inch is, to build a firearm where these "thousands" become critical quickly. Only takes using a piece of brass used in said "historical" military firearm as a head space gauge, where it might be marginal at best. Then they go watch YouTube and see someone give them faulty information about setting dies and suddenly they are approaching an unsafe realm. Tread lightly would be my 0.02.

[bsekf]

Some of you guys would go nuts if you had to deal with an Encore or Contender. They often have +/- .004 headspace, because of the location of the lug, the hole in the lug or the hole in the frame. You learn to measure your headspace and reload in accordance, or you live with poor accuracy and/or case separation. How do you dare fireform cases?

One of the beauties of being able to install your own barrel is that you can set the headspace. If you don't have the tools to measure headspace or don't know how to use them, IMHO, you have no business changing barrels.

I don't use commercial no/nogo gages or buy factory ammo. I have a couple of dedicated pieces of brass for each barrel and use 2 pieces of scotch tape for nogo. And, I make very sure my headspace doesn't exceed .002. Never had a case separation in a Savage ... yet. Headspace isn't the boogieman, I worry more about somebody trying to put a 6.5x47L in a 243. The 243 will go in a 7-08 or 308 and probably fire.... but accuracy and case life will suck!

Bill

[wbm]

I don't use commercial no/nogo gauges.... I have a couple of dedicated pieces of brass for each barrel... And, I make very sure my headspace doesn't exceed .002. Never had a case separation in a Savage

This is what I have done for 30 years also. However, I still would recommend gauges if someone asks.

[TonyBen]

When it comes to re-barreling a rifle, there are generally accepted practices that guys on forums like this agree with. But this is a public forum where people are giving advice to an anonymous individual with an unknown skill set and and unknown level of comprehension. In cases like this, I give more legalistic advice.

If this is your first re-barrel, I don't recommend using a fired or sized or new factory round to set headspace. I highly recommend using the appropriate go/no-go gauges. At the minimum, I recommend using a go gauge. It can be done with brass and has been done many times by home builders. But these home builders may have been shown how to do it by a more experienced person or they simply learned after years of experience.

My biggest concern is setting headspace too tight or under spec. Sure, it may work at first, but if you're loading to the high end of spec, you've just reduced your error window for the specified cartridge and if you made an error in your powder charge, you've just increased your chances of a catastrophic event (over-pressure). I'm not worried as much with long headspace because the type of failure (case-head separation) associated with long headspace is more of a nuisance than it is a safety concern.

When you build your first rifle or re-barrel one the first time, it's a nerve-racking experience, at least if you're like me it is. I over think things way too much, which is a good thing from a quality and safety perspective.

Most quality factory ammo, in my experience, is made to be about 0.002" short of SAAMI chamber headspace. I say quality factory ammo because all I've ever really chambered are rifles in .308/7.62 NATO which provides way too many ammo options. There's the good quality match stuff, the good quality hunting stuff, good quality US-made NATO ball ammo and then there's the third-world cheap surplus ammo made in India and Turkey and former soviet bloc countries. From this approach, I chamber customer rifles in the middle or long end of spec to accept questionable ammo from unknown suppliers.

But since you're chambering in 22-250, you don't have the added complication of unquestionable ammo. Most likely the factory ammo you get will be made in the USA and made with safe and consistent powder charges.

IF YOU ABSOLUTELY STILL WANT TO DO THIS WITH AN UNFIRED FACTORY ROUND...(I still recommend headspace gauges) and want to give yourself some wiggle room of maybe 0.002", you can screw the barrel on until it bottoms out on the case, then back it off 0.002". How do you know when you've back it off 0.002"? Well, the barrel thread pitch is 20 threads per inch, which means that one full turn of the barrel is 0.050". That means that for every degree of rotation, the barrel backs off 0.00014". So 10˚ of rotation would open up your headspace 0.0014" and 20˚ would open up your headspace 0.0028".

If you're wondering how to discern degrees without an angle finder, just think of it in clock positions Every clock position is 30˚ (1 o'clock=30˚, 2 o'clock=60˚, 3 o'clock= 90˚ etc...). So if you want to back off your barrel 15˚ (which would open up the headspace 0.002") then you can:

-Remove the extractor and ejector from the bolt face
-Insert the factory round
-Screw the barrel in until it contacts the factory round
-Make a witness mark using a sharpie at top dead center on the recoil lug or a slightly snug barrel nut and the barrel
-Then you can use a sharpie and make clock marks at the 9, 10 and 11 o'clock positions on the recoil lug or barrel nut. That will give you a visual reference as to how many degrees you're turning the barrel.
-To back off the barrel 15˚, you can loosen the barrel until the barrel witness mark is set to the 11:30 position in relation to top dead center and tighten the barrel nut. You've now set your headspace to 0.002" longer than a factory round which should give you some wiggle room.

But there is one other approach that can buy you some wiggle room. A piece of clear scotch tape (used to wrap gifts) is about 0.002" thick. Remove the extractor and ejector from the bolt face. Cut a round piece of scotch tape and place it over the bolt face or the factory round you want to use to headspace the barrel with. Make sure it's flat with no wrinkles. Insert round, screw on barrel until it bottoms out on the factory round ad snug the barrel nut. Remove the round and remove the tape and you should be set.

Clear as mud?

Tony.

[wbm]

Good write up Tony. The OP is long gone but did the right thing and opted for gauges...which he should have done given his newness to the whole process.

[RC20]

First I did mis-state the OP question.

Secondly there is a whole range of views on proper. I believe you can but I should not use the OP to justify that.

Also, this is a forum with opinions, not a company that has legal liability.

If there is one thing that irritates me has been the world ends if you set headspace wrong, the reloading books play that up as well.

When you cry wolf and put out false information (or more accurately a lie) you then weaken your standing when it comes to other areas that can be a serious risk.

If you understand head space then you can indeed properly set it. Properly being it fires.

I won't disagree that someone new probably should get at leas the no go gauge.

But as also was stated and should be repeated, fire forming is SOP and has been done innumerable times. Talk about a violation of headspace criteria.

The reality is that you simply create a unique case if your headspace is long (and it will fire)

What needs to be emphasizes, is the follow up to all that not the bugaboo on head space, that is the MINIMUM BUMP BACK.

Otherwise you create the far worse situation and that is a case head separation that can created the catastrophic gas escape and even more so in non supported firearms.

We make a big deal about over pressure. Standard proof test is 150%. No big deal.

Proof test with a case separation?

Where would that be an issue. Reloads with weakened case heads from being set back to far.

Frankly if there is an area of maximum risk in the shooting arena its rifles with unsupported cartridge heads that allow gas path escape in a major burst into he action aided and embedded (intended) by case head separation.

Ok, off the soap box.