Has anyone seen this- Youtube "Im sure" but it got me thinking. I know that most custom rifles are built with a minimum head space so they are accurate with factory ammo. And it seems as the AIs have more room than say a GAP build or Surgeon. So whats the numbers. What makes it a Match Rifle "as the first rifle in the video to jam is called" and what make a Sniper Rifle "unfailing, has to go bang everytime". And food for thought. When Reloading I do what I have learned and turn in my Full Length Resizer until the brass lets my bolt close, then load and etc....But say I have a loose chamber "read that Reliable" and I don't just run the die in untill it touches the shell holder I load like I just explained. Then doesn't that just make my Reliable action a tighter match action. I mean I reload no matter what factory stuff is awesome but I like to save money. Anyways Thoughts/Opions/Facts please. Thanks -EagleI
- Thread starter EagleI79
- Start date
Re: So what is a Reliable Head Space?
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there you go
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there you go
Re: So what is a Reliable Head Space?
That video has nothing in it that pertains to headspace. The failures in it were trigger related.
My match builds are done at .001"-.0015" over minimum. I am building an M110 and the dimension on it will be .003"-.0035" over minimum using a reamer that has .100" freebore to accommodate M118LR and clone ammo. I would consider this on the tad tight side for absolute field reliability. .004"-.005" would not be out of the question IMO, particularly considering the fact that the .mil and .LE shooters have no requirements for the rifle to shoot reloads or the spent case to be reloaded.
The .003"-.0035" dimension IMO is a decent compromise between reliability and reloadability.
That video has nothing in it that pertains to headspace. The failures in it were trigger related.
My match builds are done at .001"-.0015" over minimum. I am building an M110 and the dimension on it will be .003"-.0035" over minimum using a reamer that has .100" freebore to accommodate M118LR and clone ammo. I would consider this on the tad tight side for absolute field reliability. .004"-.005" would not be out of the question IMO, particularly considering the fact that the .mil and .LE shooters have no requirements for the rifle to shoot reloads or the spent case to be reloaded.
The .003"-.0035" dimension IMO is a decent compromise between reliability and reloadability.
Re: So what is a Reliable Head Space?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: _9H</div><div class="ubbcode-body">That video has nothing in it that pertains to headspace. The failures in it were trigger related.
My match builds are done at .001"-.0015" over minimum. I am building an M110 and the dimension on it will be .003"-.0035" over minimum using a reamer that has .100" freebore to accommodate M118LR and clone ammo. I would consider this on the tad tight side for absolute field reliability. .004"-.005" would not be out of the question IMO, particularly considering the fact that the .mil and .LE shooters have no requirements for the rifle to shoot reloads or the spent case to be reloaded.
The .003"-.0035" dimension IMO is a decent compromise between reliability and reloadability. </div></div>
Damn good answer!! Anyone else?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: _9H</div><div class="ubbcode-body">That video has nothing in it that pertains to headspace. The failures in it were trigger related.
My match builds are done at .001"-.0015" over minimum. I am building an M110 and the dimension on it will be .003"-.0035" over minimum using a reamer that has .100" freebore to accommodate M118LR and clone ammo. I would consider this on the tad tight side for absolute field reliability. .004"-.005" would not be out of the question IMO, particularly considering the fact that the .mil and .LE shooters have no requirements for the rifle to shoot reloads or the spent case to be reloaded.
The .003"-.0035" dimension IMO is a decent compromise between reliability and reloadability. </div></div>
Damn good answer!! Anyone else?
Re: So what is a Reliable Head Space?
Get a Wilson Case Gauge or RCBS Precision Mic and then sit down and measure some virgin brass, factory loads, and once-fired brass from your rifle.
Most virgin brass is at least several thousandths below go-gauge dimension. Factory loads are the same.
Headspace refers to dimension of your chamber. Magnum cases, which used to primarily be rimmed, were setup to headspace on the case rim; not good for accuracy. Nowadays, any decent gunsmith sets up a precision rifle in rimmed magnum chambering to headspace on the shoulder.
SAAMI and go-gauge dimensions are guidelines. Just like tight-neck chambers prohibit standard cases that haven't been neck-turned from chambering, under go-gauge dimension may mean ammunition you didn't make might not chamber in your rifle.
Personally, I have seen in my rifles that a short oal chamber, go gauge plus .0005" to .001" give best accuracy. Have never had a problem with factory or virgin handloads. Can be a problem if you don't keep cases trimmed. Probably have to size your cases about every 3 firings. A type S FL bushing sizer allows you to neck size and then set for FL sizing so use one of those with bushing you favor...
A minimum oal chamber will deliver much longer brass life for obvious reasons. You definitely want any rimmed magnum ctg to headspace on the shoulder. It is worth having barrel set forward to obtain the min oal dimension. Best mod you can do for the money after adjusting your trigger...
Get a Wilson Case Gauge or RCBS Precision Mic and then sit down and measure some virgin brass, factory loads, and once-fired brass from your rifle.
Most virgin brass is at least several thousandths below go-gauge dimension. Factory loads are the same.
Headspace refers to dimension of your chamber. Magnum cases, which used to primarily be rimmed, were setup to headspace on the case rim; not good for accuracy. Nowadays, any decent gunsmith sets up a precision rifle in rimmed magnum chambering to headspace on the shoulder.
SAAMI and go-gauge dimensions are guidelines. Just like tight-neck chambers prohibit standard cases that haven't been neck-turned from chambering, under go-gauge dimension may mean ammunition you didn't make might not chamber in your rifle.
Personally, I have seen in my rifles that a short oal chamber, go gauge plus .0005" to .001" give best accuracy. Have never had a problem with factory or virgin handloads. Can be a problem if you don't keep cases trimmed. Probably have to size your cases about every 3 firings. A type S FL bushing sizer allows you to neck size and then set for FL sizing so use one of those with bushing you favor...
A minimum oal chamber will deliver much longer brass life for obvious reasons. You definitely want any rimmed magnum ctg to headspace on the shoulder. It is worth having barrel set forward to obtain the min oal dimension. Best mod you can do for the money after adjusting your trigger...
Re: So what is a Reliable Head Space?
Now that you edited and changed the question in the original post, bignada's post is right on.
Now that you edited and changed the question in the original post, bignada's post is right on.
Re: So what is a Reliable Head Space?
A light crush fit on the brand of brass I intend to use and everything else falls into place.
A light crush fit on the brand of brass I intend to use and everything else falls into place.
