For better accuracy in M1A, turn off the gas?

eaglesnester

eaglesnester

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Brainstormen here. I should think that turning off the gas on a M14 and getting things quiet when the bullet leaves the muzzle would improve accuracy a whole lot. I think by going manual the M305 would shoot just like any other bolt gun. What say all of U experienced M14 shooters that roll yur own ammunition? I think this is so and I do believe I will develop some 165 grain Barnes TTSX loads. Also by turning off the gas it would seem that a shooter would be able to increase MV and loads without fear of damaging the Oprod or receiver up to a point. Thinking that 2750 or 2800FPS would be doable without fear of damaging the rifle with the gas off. Lets hear some comments from those that have experience with this rifle.

Cheers&Tighter Groups: Eaglesnester
 
Can only speak for myself, but its like two different rifles.
I have the gas turned off for all group shooting and find it makes a huge difference.
Also lets you play with heavier bullets and loads. I AM NOT RECOMMENDING THAT YOU DO THAT, you make your own choices :)
Having the gas turned off eliminates many variables, is way easier on the brass, and if your shooting for groups it gives you consistency to a degree, essential if you are developing loads.

Having the gas on is still the most fun you can get for your money this side of Amsterdam.
Tight groups.
 
Look-up slow motion video of an M14 firing, the bullet is long gone before the op-rod even starts to move, so an increase in accuracy would be negligible. You need to cycle the action either way and its the actions return to "mechanical zero" that determines consistancy.
As far as hammering the action with the heavier bullets, yes the op-rod takes a harder hit with the higher pressures, but you are also subjecting your bolt and receiver to this abuse, so it can still be harmful, gas on or off.
The Chinese M14's can have loose tolerances and soft metals, you really want to be sure you are getting full locking lug engagement on both lugs to be safe.

If you want a bolt action 308, get a bolt action 308. An M14 is a battle rifle, always has been, always will be, no matter what we do to mod them or how we use them, it will always be a battle rifle.
Don't expect some miracle to happen because you turned the gas off, it will still be the same rifle.

Instead, learn the action for what it is, how it works and what works to increase accuracy. But, chasing accuracy in an M14 can get expensive.

If this doesn't interest you, buy a rifle to suit your need.
 
Lost...again said:
Can only speak for myself, but its like two different rifles.
I have the gas turned off for all group shooting and find it makes a huge difference.
Also lets you play with heavier bullets and loads. I AM NOT RECOMMENDING THAT YOU DO THAT, you make your own choices :)
Having the gas turned off eliminates many variables, is way easier on the brass, and if your shooting for groups it gives you consistency to a degree, essential if you are developing loads.

Having the gas on is still the most fun you can get for your money this side of Amsterdam.
Tight groups.
Click to expand...
Totally agree with you on the above, way more fun with the gas on but does not seem to be nearly as accurate. Did a 1.5 inch 4 shoot group today at 100 meters with one flyer. MV was around 2750 for the 4 shot group, using 45grains of IMR4895 and a 165 grain Barns TTSX. Me thinks with a little more load development I just might get a 1 inch group,the flyer chroned out at 2650FPS which could account for the flyer. It went way low and spoiled what was starting to look like a good group through the spotting scope. My fired brass measures out with a hornady head space gage at the shoulders at 1.633.
Which would indicate to me that I have virtually no head space issues. My Norenco is one of the newest batches from Marstars. It suffers from none of the previous foibles such as bolts that do lock up on both sides, improperly registered barrels, safety's that are difficult or impossible to operate, flash hiders not on straight, and on and on. Only complaint is that the trigger is horrible, but hey its a battle rifle.
 
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orthoboy said:
So pardon my noob question but I have a new SA m1a super match. How or why do I need to adjust the gas?
Click to expand...

With your SuperMatch .6-.7 MOA will be the norm with quality factory ammo, i dont know if you would gain much accuracy, this rifle is off the bat extremely accurate... JP.
 
Lost...again said:
Can only speak for myself, but its like two different rifles.
I have the gas turned off for all group shooting and find it makes a huge difference.
Also lets you play with heavier bullets and loads. I AM NOT RECOMMENDING THAT YOU DO THAT, you make your own choices :)
Having the gas turned off eliminates many variables, is way easier on the brass, and if your shooting for groups it gives you consistency to a degree, essential if you are developing loads.

Having the gas on is still the most fun you can get for your money this side of Amsterdam.
Tight groups.
Click to expand...

Why the caveat, LA? Can this be potentially harmful to the M1A? I am of two minds on it too...I do not like the idea of 'two rifles in one' because when I am out hunting I want to know EXACTLY what my gun does and I want my shooting routine to be instinctive and automatic when I am pulling the trigger on game.
But ya know....it would be nice not to have to chase brass sometimes...
 
A load develloped gaz shut, wont react the same gaz on, this is bad thing for an important shot... I maybe wrong but the nature of the beast is SA action... JP.
 
jonh172 said:
Look-up slow motion video of an M14 firing, the bullet is long gone before the op-rod even starts to move, so an increase in accuracy would be negligible. You need to cycle the action either way and its the actions return to "mechanical zero" that determines consistancy.
As far as hammering the action with the heavier bullets, yes the op-rod takes a harder hit with the higher pressures, but you are also subjecting your bolt and receiver to this abuse, so it can still be harmful, gas on or off.
The Chinese M14's can have loose tolerances and soft metals, you really want to be sure you are getting full locking lug engagement on both lugs to be safe.

If you want a bolt action 308, get a bolt action 308. An M14 is a battle rifle, always has been, always will be, no matter what we do to mod them or how we use them, it will always be a battle rifle.
Don't expect some miracle to happen because you turned the gas off, it will still be the same rifle.

Instead, learn the action for what it is, how it works and what works to increase accuracy. But, chasing accuracy in an M14 can get expensive.

If this doesn't interest you, buy a rifle to suit your need.
Click to expand...
Had a look at the slomo video of the M14 barrel and action during shooting and the above post is correct, The bullet would appear to have already left the muzzle by the time the oprod starts to move. That barrel sure does whip some, good case for bedding. I would still think though that I am correct that turning the gas off would prevent damage to op rod and receiver damage from op rod slamming into receiver during cycling with a 165 grain bullet Traveling at 2700 FPS. Wondering though if the pressure sufficient to get a bullet up to 2700FPS would eventually damage the bolt, bolt lugs, chamber, and bolt notches in the receiver.
 
eaglesnester said:
Me thinks with a little more load development I just might get a 1 inch group,the flyer chroned out at 2650FPS which could account for the flyer. It went way low and spoiled what was starting to look like a good group through the spotting scope.
Click to expand...

Hey Eagle - I don't know if you have tried this but my recent experience says that bedding and barrel tension is an important factor in getting these rifles to shoot without the flyers and stringing (once they are warmed-up). I have had to adjust my barrel tension to get rid of flyers and I notice that Pop bedded his, and used the coat hanger method to achieve the correct tension. Just a thought...

Also while I'm sure you have done your load development, 165 grains of 4895 under a 165 grain pill would be really hot for my rifle which likes it more at the 40-ish grains for accuracy. Makes me curious what MV I'm getting with my loads. Will have to ask my buddy Rodauto to set up his chrony next time at the range.
 
Installing an adjustable gas plug would work too if running heavy bullets to prevent hammering the oprod, a buffer is also a good idea.

An increase in fps May be negligible also as you're not tapping that much gas; just enough to unlock the bolt; and far enough down the barrel that your bullets are getting up to speed, but I've never tried so i'd be interested in seeing some numbers if u get a chance to experiment!
 
Shutting off the gas doesn't turn a semi-auto into a bolt action target rifle. It just stops the rifle from functioning as a semi-auto.
If you want 2800 fps with a 165 use the right powder. It's not unusual, but you will be using max or slightly above max loads according to Barnes' site.
The bullet being out of the barrel before anything else happens is how semi-autos work. The pressures must be reduced before the action can open of very bad excrement will happen to the shooter. Think physics.
An M305 is not and never was an M-14.
 
What the hell is the point of buying a semi auto rifle, and turning it into a straight pull bolt action? If whole point of accurizing an M14 is to make it an accurate SEMI AUTO rifle. If you want an accurate manual rifle, get a bolt gun.
 
orthoboy said:
So pardon my noob question but I have a new SA m1a super match. How or why do I need to adjust the gas?
Click to expand...

well..... I only shut the gas off when I'm cleaning the barrel. it's an ol trick from the military manuals and is done so no bore cleaner and crud get in your gas system during bore cleaning.
it was also a feature that enabled the firing of rifle grenades
it's popularity as an 'accuracy mode" for these rifles kinda amuses me ;)
it is a must to shoot with gas off if you are measuring the brass with a precision mic
but otherwise I'd kinda agree with the buy a bolt gun statement
 
I don't know about current rifles, but National Match M14's(and M1A's) of the past had their spindles locked in the "open" position.

The closed position was for launching rifle grenades, and was apparently hard on the rifle....
 
IMO, especially after what everyone has stated, you are not accomplishing much by turning your gas off. That bullet is long gone before the lil bit of gas is cycled and parts start moving. Accuracy really is negligible, so just work up a load properly. Might have to step down in bullet weight to achieve the velocity you need. 45grs of 4895 is 1gr above Barnes data...
 
let's be careful here gentlemen.
the cautions and pitfalls of reloading for these rifles is widely written about.
screwing around with max loads and gas system monkeying is a sure fire way to exceed max pressures and give yourself or the shooters around you a very bad day.
as for shutting off the gas.... I've seen it done with silencer/suppressor and light subsonic loads..... works well, videos are on you tube.
and for reloaders who want to fire form cases and for measuring max expansion of brass with a precision mic because it's the only way to ensure the brass has finished expanding prior to ejection.
it can also be helpful when trying to diagnose some rifle issues as well.
but for general shooting, for accuracy..... if you need to do this, buy a bolt gun you will be far less frustrated :D
 
Thanks for all the input. Will cut back on loads try different powder, leave gas on and keeps MV down to 2600FPS using 168 gr pills . WIth ChiCom Nato 7.62X51, 147 grain pills was surprised, it chronied at 2800FPS 10 feet from muzzle
 
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I'm gonna say no LOL
simply because with a bolt gun, the round is locked in the chamber until the shooter manually turns the bolt by it's handle
with an m14/m1a /m305 the bolt , when fired with the gas off, may still move in it's lugs .

will it fire a round loaded from the magazine in a non semi automatic mode with the gas shut off .. yes....... but that's not describing a bolt gun
so my answer is still no.
 
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