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questions about upper and lower receivers

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Replied by TrapperJohn on topic Re: questions about upper and lower receivers

Yes and no. Some like the 458SOCOM will work in the regular 5.56 mags but others like the 6.8spc will have their own magazine. You will also have to replace the bolt and in some cases the whole BCG(bolt carrier group).

As far as the building aspect goes. You do need some tool's but not many. You will need a barrel nut wrench and it is a good idea to get some gunsmithing screw drivers a Vise and some other thing's but you will use them later so it's best to have them anyway. Most of it is really easy to put together.

Take a look at youtube. Search building upper, building lower and install free float tubes and that should help a lot.


And yes with the right parts you can build a better rifle then what you could buy. Like I said don't worry about the building part that is the easy part. Paying for the parts is the part that sucks!
12 years 8 months ago #8638

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Replied by TrapperJohn on topic Re: questions about upper and lower receivers

By the way don't worry about asking questions. I don't mind. I love AR's and if I can help someone I am more then happy.
12 years 8 months ago #8639

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Replied by TrapperJohn on topic Re: questions about upper and lower receivers

Something else I thought about. The rifle twist. You need to figure out what type of bullets you are going to be shooting. If you are shooting heavy bullets go with a fast twist like 1/7 or 1/8. The military uses a 1/7 twist. You also want to go with a 5.56 and not 223. The 223 cannot handle the high pressures of the 5.56 but the 5.56 can handle the lower pressure of the 223. Don't believe anyone who says they are the same they are not. The 5.56 and the .223 on the outside are identicle but on the inside is where there is a differance. The 5.56 is thicker on the inside to handle the high pressure. Do a google search for the "ammo oracle" for more info on this.
12 years 8 months ago #8642

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Replied by derfarhar333 on topic Re: questions about upper and lower receivers

So could I cheat a little bit and buy a complete upper receiver and a stripped lower receiver and all the different parts, assemble the lower and then attach it to the upper and have a functioning rifle. Not just functioning but accurate and reliable as well?
12 years 8 months ago #8657

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Replied by TrapperJohn on topic Re: questions about upper and lower receivers

Yes you could. But sometimes you can have a problem mating the two. With one of my rifle's I bought a LMT MRP upper and a LMT lower to go with it but the two did not fit correctly and I had to take sand paper to the lower and shave off a little for them to fit. Even today it is still a little tight but the fit is nice. With any build that I did usually the upper and lower were a little loose but after that LMT experience I decided I would go with a upper and lower that were made to fit together like the SunDevil I told you about.

Spikes also sells a upper and lower that are mated together.

www.spikestactical.com/new/z/spikes-tact...lower-set-p-377.html

I am not trying to talk you out of this I just want to let you know what you might be in for. Many do not have the problems that I came across.

One thing someone else pointed out that it might be better to just buy a complete rifle and modify it later on. I work on my rifles and I do builds for others so sometimes I forget that it just might be better to buy a rifle and go from there.
12 years 8 months ago #8660

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Replied by TrapperJohn on topic Re: questions about upper and lower receivers

This got posted in another thread but it belongs here:

By LebbenB
I respectfully disagree with the "build it yourself" option for the OP. For someone new to the platform, all the part choices and options can be a bit dizzying and confusing. Having little experience with ARs, a new owner runs a higher risk of purchasing inferior parts. Also, if the assembled gun doesn't perform to spec the OP has no recourse, ie: a manufacturer's warranty, to fall back on.

For a new AR shooter, I would say figure out what you want to use the rifle for. Determine the best caliber for the task(s), figure out what barrel length would work best, and what features you require. Then purchase the rifle from a reputable maker. Once you get some experience with the AR, you can start modifying the rifle with different calibers, barrel lengths, forends, and stocks, et al.

Good luck! And happy shooting.

This is actually good advice!
12 years 8 months ago #8661

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Replied by derfarhar333 on topic Re: questions about upper and lower receivers

I appreciate the honesty of your opinions. That's why I joined. ;) If I go the buying route I am thinking about either the sig 516 or a stag arms model 2 or 3. Would like to stay at $1000 or under.
12 years 8 months ago #8664

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Replied by TrapperJohn on topic Re: questions about upper and lower receivers

You might want to tak a quick look at this.
It is a Colt LE M4 for $1,200. I know it is a little more then you wanted to spend but Colt does make good products. It also has the 1/7 twist that I personally like.
www.budsgunshop.com/catalog/product_info.php?products_id=60386

The SIG is nice! I have only heard a lot of good things about them but I have never owned or shot one. Maybe someone else here can chim in and give an opinion.

As far as Stag goes. I would personally get something else. But that is my opinion and I will just leave it at that.

For a $1,000 you do have some options but $1,300 or less will get you a better rifle.
12 years 8 months ago #8665

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