Changing the barrel on a M&P 15 Sport

[cyphertext]

Chattanooga I don't hate the gun at all. I just realize that if I want to put optics on it, and I do, the FSB will be in the way. That is all this post is mainly about.

Why don't you try it first before you do anything to the rifle?... you just may find that the front sight post is not in the way of anything.

If you want a red dot, you can set it up for absolute co-witness or lower 1/3rd as shown above. When using a red dot correctly, with both eyes open and focusing on the target, the front sight is not in the way... I don't even notice it.

And with a scope, if you are at 4x or higher magnification, you don't see the front sight due to the focal point of the scope.

The front sight is not in the way on any of my rifles.

 

[ChattanoogaPhil]

Chattanooga I don't hate the gun at all. I just realize that if I want to put optics on it, and I do, the FSB will be in the way. That is all this post is mainly about.

I know.
The "" in my post indicated humor on that sentence.

The larger message to all guys thinking about getting their first AR is to ponder a bit about what the rifle will actually be used for and what configuration best fits. Otherwise, folks often pick the cheapest in the lineup, Sport, then start dreaming up stuff like grinding off the front sight and replacing parts on the rifle. The end result is often an AR parts box and a credit card bill significantly more than buying a rifle in a more accommodating configuration to begin with.

 

[turbo38gn]

He has the gun now, pick out a new upper from somewhere like PSA for a good price. ....... and what he wants, $ell the old upper ..... no parts left over and out of pocket expense is minimal if at all...

 

[ChattanoogaPhil]

He has the gun now, pick out a new upper from somewhere like PSA for a good price. ....... and what he want, $ell the old upper ..... no parts left over and out of pocket expense is minimal if at all...

That's not how it works.
Get a new upper. Find out how little anyone will pay for the Sport upper. Figure might as well keep the upper. AR parts box starts out with an upper in it and grows from there.

 

[McE]

Remove flash hider, punch out pins on the front sight block, replace with a low profile gas block, replace flash hider, the end.

 

[crracer_712]

That's not how it works.
Get a new upper. Find out how little anyone will pay for the Sport upper. Figure might as well keep the upper. AR parts box starts out with an upper in it and grows from there.

+1, it's amazing what other peoples parts are worth compared to yours.... I don't get rid of much of anything, because I hate selling, the process of it. If I want to relieve myself of something I generally either throw it away or give it away. But gun stuff, well, that's kind of an unintended stock pile sort of thing.

 

[kwikvette]

As posted above;

Buy new upper, swap in new upper in place of old upper. Buy lower parts, buy lower, put together. Now you have 2 AR's!

Do this a few times for practice

 

[Chinook1717]

i think I'm going with McE (among others) suggestion and swapping out the gas block. Besides who needs a bayonet lug??

 

[crracer_712]

i think I'm going with McE (among others) suggestion and swapping out the gas block. Besides who needs a bayonet lug??

If you go this route, I'd suggest having a gunsmith do it. Those pins that hold the FSP are installed from one side and must come back out from that same side, and they are usually tight. Since you are new to AR's I doubt you would have the necessary tools to do the job and it probably won't cost you but ~50 bucks at most for a gunsmith to do this for you.

 

[Chinook1717]

Crracer,

All I would need is a set of punches and a hammer to take it off. Watched several youtube video's on it. Granted I probably wouldn't do it as fast as they did but it's rather simple as most of them tell you which way to turn the barrel to punch them out from.
But I do understand you point. If it didn't appear that easy I wouldn't do it myself.

 

[crracer_712]

Reminds me of the time I needed to change the drive belt on my John Deere GT275, requires removing the Electric PTO. Watched videos and it was all magic in how they simply removed the crankshaft bolt and the PTO all but fell off.

Me, removed bolt fine, PTO wouldn't budge! I gave up on it for awhile, soaked it with some penetrating oil, called a friend who works on mowers and told him the story and he laughed. He said, yeah, he's seen videos and replied 'but here in the real world....' Well, I did get it off, but it wasn't anything like the videos.

Just passing on some advice from my gunsmith. I noticed he had one of those plastic blocks laying on his table that you lay the barrel/FSP in. I pointed to it and he say yeah, some kid was wanting to remove his FSP, had bought this block and never could budge the pins. So the kid brought the rifle to him, and just gave him that plastic block. He says that block is pretty neat, but doesn't use it. He opens a drawer and pulls out a piece of babbitt steel, about an inch thick. Says he uses that to back up the FSP as it doesn't bounce all over the place like a piece of plastic will, yet the steel is soft and won't mar the surface of the rifle.

I've no doubt you could get it apart, hopefully its a breeze as they are on those videos.

 

[wurger]

Remove flash hider, punch out pins on the front sight block, replace with a low profile gas block, replace flash hider, the end.

Easier said than done sometimes. I tried to remove the front sight on my Sport and could not get the dang pins out. Took the rifle to a local gunsmith and he couldn't get the pins out either. We had to cut the front sight off the rifle.

 

[turbo38gn]

I got faith in Chinook... he sounds pretty confident.. that's the 1st step.. I remember my 1st time knocking the pins out... just need a good punch and hammer.. good support for the front sight and don't be bashful.. also, will need to punch out the pin for the gas tube... may want to have another pin, just in case or even a gas tube... that's always an adventure, more of a PITA doing than the sight..

 

[Chinook1717]

Thanks turbo38gn. I bought the gas block on Friday. Just need to find me a good flip up front site before I swap it out. Then once that is done I will search high and low and over think what optic to get.

 

[ChattanoogaPhil]

If you're still considering buying a different upper on budget, here ya go...

Introduction Pricing - Radical Firearms Receiver Sale | Primary Arms

 

[turbo38gn]

If you're still considering buying a different upper on budget, here ya go...

Introduction Pricing - Radical Firearms Receiver Sale | Primary Arms

Wow... that's a smoking deal..

 

[Chinook1717]

Yes it does look like a great deal but why am I going to take a $550.00 AR and then spend $200 to swap the barrel?? There is a video on youtube everyone needs to see. I believe it's called "stop buying AR's". They guy isn't saying people shouldn't own them so please do get mad. His point is don't buy an AR for say $850 and then spend around $1450 changing out everything to keep up with the 'cool' kids. He is talking build your AR if you are going to swap out 'everything' instead of buy. So basically I'm saying after the optics I'm more or less done with swapping out anything more on this one. NOW not saying I don't want to be like the 'cool' kids, but to do that next one will be ground up build.

 

[turbo38gn]

Yes it does look like a great deal but why am I going to take a $550.00 AR and then spend $200 to swap the barrel?? There is a video on youtube everyone needs to see. I believe it's called "stop buying AR's". They guy isn't saying people shouldn't own them so please do get mad. His point is don't buy an AR for say $850 and then spend around $1450 changing out everything to keep up with the 'cool' kids. He is talking build your AR if you are going to swap out 'everything' instead of buy. So basically I'm saying after the optics I'm more or less done with swapping out anything more on this one. NOW not saying I don't want to be like the 'cool' kids, but to do that next one will be ground up build.

not a good post....... maybe you should reread your 1st post because we have responded to your original question. This isn't about being "cool". It's about options.... changing out a complete upper allows for having a completely different Ar... not being "cool" ... It appears you are looking to be the "cool kid" and oh so smart.. and for the record, you didn't buy an AR for $850 and look to do $1450 worth of "upgrades". Also, unless you want 2 AR's, you don't have to build a complete gun from the ground up, just need to build an upper and drop it on your existing lower.

 

[Chinook1717]

I started this post due to the fact I wanted to put optics on my AR but didn't want the A2 post 'in the way'. I thought I would have to swap barrels to do this hence the name of the post. Not I found our from you great folks that all I needed to do was swap out my gas block and I would be good to go. But why take a base line gun (I think we can all agree that this is what the M&P sport is) and put new grip, bolt, charging handle, rails, stock, barrel and the like when we could have bought the parts for less than we have in the stock gun and all the upgrades. As far as having a different barrel and have a different gun, why not get another lower to go with that barrel and you will be on your way to a second AR. Sorry you can never have too many AR's. Anyone agree??

 

[cyphertext]

Have you even shot the gun yet? Do you have the optic that you want on the rifle in hand?