A question about AR gas blocks

[Ironbar]

I've finally narrowed down my search for an AR upper, but I need some advice. Having a front sling swivel is a must-have. But it seems that all the uppers that come with the sling swivel have the standard AR front sight post. I'm trying to avoid this as I intend on scoping the rifle once it's put together.

All the uppers without the front sight obviously have gas blocks, but none of them seem to have a mount for a swivel. All the aftermarket gas blocks that have a quad rail or low Picatinney rail run upwards of $70-80, and I'd have to buy the damned sling swivel on top of that. I find this too cost prohibitive.

For those of you that have scoped your AR's, does the front sight interfere with your sight picture through the scope? Do you know of any inexpensive fixes for the gas block problem?

Help!

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[Unka-Boo]

anything above 2 power you wont see the post....and you can always cut the sight off of the gas block, used to be a common thing to do for FF tubes before all the aftermarket blocks started showing up

 

[krivey]

You could run a rifle length quad rail and put a sling swivel at the end. When I ran a scope with a standard front sight I couldn't see the post but I did have a reduction in brightness. Almost like a shadow. You may not have a problem at all.

 

[Cameron72]

When your are all strapped in with the sling to fire your AR you may end up putting lateral pressure on your barrel so your shot may be off. That's why their are free float front tubes.

 

[Ironbar]

Well, I finally pulled the trigger so to speak. I've ordered all the parts and will begin the build when I get the needed armorers tools.

I bought the Palmetto State Armory Magpul CTR lower build kit, a drop-in 3.5 lb trigger, and complete 20" HBAR A3 upper with Nitride barrel in 5.56. It will all be built on an Anderson stripped lower. I already have a scope and rings for it. I'll probably give it a couple more tweaks before I'm done, but I'm hoping this will give me a good all-around rifle for what I want it for!

 

[Boboclown]

Might need the vise block. And a vise if you don't have one already.

Free float or not? Just curious.

 

[Ironbar]

Vise block is on the way. Didn't go with a free float but may in the future.

 

[ron]

The number one accuracy improvement for the AR is a
free float tube. IMHO As stated in previously different
sling tension can make a big difference at the target.
I like a set up with a low profile gas block and a free float
tube passing over the gas block. Putting the sling swivel
on the float tube. And a 'backup' flip up front sight on the
end of the float tube. Yankee Hill Machine makes
excellent float tubes, gas blocks and flip up sights. YHM
products are well made and not too expensive.

 

[Boboclown]

The number one accuracy improvement for the AR is a
free float tube.

This, sort of. With a non-free float handguard anything you do will affect point of impact. If you use a bipod, going from using a bipod and not using one eill change the point of impact. Or different pressure on the bipod each time will change it.

It could be accurate without a free float handguard, but it won't be as consistent.

 

[Charliehorse]

The number one accuracy improvement for the AR is a
free float tube. IMHO As stated in previously different
sling tension can make a big difference at the target.
I like a set up with a low profile gas block and a free float
tube passing over the gas block. Putting the sling swivel
on the float tube. And a 'backup' flip up front sight on the
end of the float tube. Yankee Hill Machine makes
excellent float tubes, gas blocks and flip up sights. YHM
products are well made and not too expensive.

Absolutely agree.

 

[liquidsys]

This, sort of. With a non-free float handguard anything you do will affect point of impact. If you use a bipod, going from using a bipod and not using one eill change the point of impact. Or different pressure on the bipod each time will change it.

It could be accurate without a free float handguard, but it won't be as consistent.

I agree, except with your last sentence. At the end of the day, accuracy IS consistency. It doesn't matter if your rifle shoots 1" left, as long as it does it every single time.

 

[Boboclown]

I agree, except with your last sentence. At the end of the day, accuracy IS consistency. It doesn't matter if your rifle shoots 1" left, as long as it does it every single time.

But if it shoots right when going from bipod to offhand, but groups are the same, the POI isn't consistent. That's where the free float comes in. If free floated, the POI <should> (shooter's skill may vary) should remain consistent from using a bipod to not using it.

I probably should have worded it better.

 

[liquidsys]

But if it shoots right when going from bipod to offhand, but groups are the same, the POI isn't consistent. That's where the free float comes in. If free floated, the POI <should> (shooter's skill may vary) should remain consistent from using a bipod to not using it.

We're now saying the same thing Bobo

Doesn't matter where the bullet hits, as long as it hits there every single time. That's accuracy. =)
Without free floating, he'll have a hell of a time getting that consistency. Especially if he moves from bipod to tensioned sling to free hand and back again.

 

[Boboclown]

Pretty much, just didn't word it the way I should have.

 

[Ironbar]

Gentlemen, the point is moot. I purchased an upper with a standard front sight/gas block. I intend on using the rifle to its fullest potential. I am a rifleman not a bench rest shooter. My personal feeling is that bench rest shooting is lazy.

Yeah, maybe all you're looking for is a day on the bench, shooting sub MOA groups. My preference is learning and keeping the skills needed to engage a 20 inch target out to the rifleman's quarter mile. We'll see what this rifle brings me in the way of accuracy. If it unacceptable then I'll consider upgrading to a free float handguard. For now, I'll make do with what I ordered and do the best I can with it.

I'll post a range report when I get it all together.

 

[Boboclown]

Well, I don't do bench shooting only. I just prefer consistency with the POI. Even changing your grip can affect it, however slight the change may be. I shoot off the bench off-season, so when my scope is sighted in I don't want to have to sight it in again.

 

[ron]

Gentlemen, the point is moot. I purchased an upper with a standard front sight/gas block. I intend on using the rifle to its fullest potential. I am a rifleman not a bench rest shooter. My personal feeling is that bench rest shooting is lazy.

Yeah, maybe all you're looking for is a day on the bench, shooting sub MOA groups. My preference is learning and keeping the skills needed to engage a 20 inch target out to the rifleman's quarter mile. We'll see what this rifle brings me in the way of accuracy.
If it unacceptable then I'll consider upgrading to a free float
hand guard. For now, I'll make do with what I ordered and
do the best I can with it.

I'll post a range report when I get it all together.

As a rifleman I have learned the importance of using the sling
for stability. Yesterday I shot a High Power Rifle match. Using
a 20 inch AR 'Service Rifle' with iron sights slung in the prone position at 600 yards. The use of sling is fundamental to a
steady shooting position. An AR with free float hand guard is imperative. Varying sling tension will greatly degrade accuracy without the floated front hand guard.

 

[liquidsys]

As a rifleman I have learned the importance of using the sling
for stability. Yesterday I shot a High Power Rifle match. Using
a 20 inch AR 'Service Rifle' with iron sights slung in the prone position at 600 yards. The use of sling is fundamental to a
steady shooting position. An AR with free float hand guard is imperative. Varying sling tension will greatly degrade accuracy without the floated front hand guard.

This is basically exactly the point I was trying to make earlier. Your example illustrates it a little better, I think.

 

[U8395279]

As Unka-Boo says, cut down the front sight. Nice solid gas block with sling swivel and no a standard sight will not interfere with magnified optics.

If you don't want to do it yourself it doesn't cost that much and I'm sure there is someone on this site that does it but here ref.
https://www.adcofirearms.com/shopservices/shop_qnew.cfm?code=Shave Standard FSB

.

Surely there must be some local gunsmiths here in Oregon, who could do this sort of work? Shipping out of state for something so minor as this would seem like a waste.

I would have to think that there must be someone available in the Willamette Valley that could help with such minor AR work. I used to know a gunsmith in Eugene who could handle small work like this, but he has unfortunately retired.

.

 

[U8395279]

Did you even read want I wrote?

Yes, I read every letter of every word that you wrote.

I don't think that he has to go to a website for a company in Ohio. There surely must be some local gunsmiths or companies that could handle doing this.

.