How important is it to have a matched upper and lower? I have an Alexander Arms GSR upper on order (hopefully I get it this year) and an SI Defense billet lower. Still a good combination?
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Re: uppers and lowers
sounds good then, thanks for the help
sounds good then, thanks for the help
Re: uppers and lowers
Fit will vary. The great thing about the AR platform is modularity and interchangeability. This is possible due to relaxed manufacturing tolerances. As previously stated, you are usually fine but once in a while you will come across parts that are at the extreme end of the tolerance stack-up and you will get an exceptionally tight fit or a rather sloppy fit.
In my experience, the AR's I have pieced together from mixed/matched uppers and lowers have leaned to the loose side of the fitment spectrum. If tight upper/lower lock up is important to you, I would recommend a lower that has a set screw to take up the upper/lower play like the Seekins SP223.
Fit will vary. The great thing about the AR platform is modularity and interchangeability. This is possible due to relaxed manufacturing tolerances. As previously stated, you are usually fine but once in a while you will come across parts that are at the extreme end of the tolerance stack-up and you will get an exceptionally tight fit or a rather sloppy fit.
In my experience, the AR's I have pieced together from mixed/matched uppers and lowers have leaned to the loose side of the fitment spectrum. If tight upper/lower lock up is important to you, I would recommend a lower that has a set screw to take up the upper/lower play like the Seekins SP223.
Re: uppers and lowers
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Flynn</div><div class="ubbcode-body">If they fit well, they're a good combination. Usually, it doesn't matter much, but occasionally you get uppers/lower fits that are excessively tight or loose. Loose isn't a big deal, but it bothers some folks. </div></div>
I would agree only to the point that loose doesn't matter as long as you're not concerned with precision shooting. I realize that precision shooting isn't necessarily on the minds of most of those whom are running the AR platform but you can still shoot precision to a degree. Depending on the individual's skill level and the amount of slop in the mating of the upper to the lower could result in a clean "head shot" or a "whistle over the shoulder," as my dad always liked to say, when shooting at distance. But for the average shooter who doesn't normally shoot past 100-150 yards, center mass should be achievable no matter the fitment. All in all, I'm just saying that whether loose fitment is an issue is dependent on your usage and application of the tool itself. Just my opinion.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Flynn</div><div class="ubbcode-body">If they fit well, they're a good combination. Usually, it doesn't matter much, but occasionally you get uppers/lower fits that are excessively tight or loose. Loose isn't a big deal, but it bothers some folks. </div></div>
I would agree only to the point that loose doesn't matter as long as you're not concerned with precision shooting. I realize that precision shooting isn't necessarily on the minds of most of those whom are running the AR platform but you can still shoot precision to a degree. Depending on the individual's skill level and the amount of slop in the mating of the upper to the lower could result in a clean "head shot" or a "whistle over the shoulder," as my dad always liked to say, when shooting at distance. But for the average shooter who doesn't normally shoot past 100-150 yards, center mass should be achievable no matter the fitment. All in all, I'm just saying that whether loose fitment is an issue is dependent on your usage and application of the tool itself. Just my opinion.
Re: uppers and lowers
I'd like head shots up to like 200yds...after that center mass is good enough, only going up to like 600yds tops. I'm not the best shot, I'm not the worst shot either.
I'd like head shots up to like 200yds...after that center mass is good enough, only going up to like 600yds tops. I'm not the best shot, I'm not the worst shot either.
Re: uppers and lowers
On a different note, anybody have any idea on wait times for Alexander Arms?
On a different note, anybody have any idea on wait times for Alexander Arms?
Re: uppers and lowers
I have mixed and matched uppers and lowers and they worked just fine. I have used a DPMS lower on a Bushmaster upper. And also a seekins lower on a DPMS upper. The seekins upper was a tight fit on the DPMS upper but I think that was due to the coating on the DPMS upper.
I have mixed and matched uppers and lowers and they worked just fine. I have used a DPMS lower on a Bushmaster upper. And also a seekins lower on a DPMS upper. The seekins upper was a tight fit on the DPMS upper but I think that was due to the coating on the DPMS upper.
Re: uppers and lowers
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: importsstillsuck</div><div class="ubbcode-body">I'd like head shots up to like 200yds...after that center mass is good enough, only going up to like 600yds tops. I'm not the best shot, I'm not the worst shot either. </div></div>
Something would be really wrong if you arent able to get that kind of accuracy. I have seen several AR's shoot .5 moa at 100-200 that are basically stock out of the box. one was a regular old olympic arms. Work up some reloads or stick to quality ammo and it will shoot great.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: importsstillsuck</div><div class="ubbcode-body">I'd like head shots up to like 200yds...after that center mass is good enough, only going up to like 600yds tops. I'm not the best shot, I'm not the worst shot either. </div></div>
Something would be really wrong if you arent able to get that kind of accuracy. I have seen several AR's shoot .5 moa at 100-200 that are basically stock out of the box. one was a regular old olympic arms. Work up some reloads or stick to quality ammo and it will shoot great.
Re: uppers and lowers
Sounds good then...should be $3000+ well spent lol
Sounds good then...should be $3000+ well spent lol
Re: uppers and lowers
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BigtimeAub</div><div class="ubbcode-body">I would agree only to the point that loose doesn't matter as long as you're not concerned with precision shooting. I realize that precision shooting isn't necessarily on the minds of most of those whom are running the AR platform but you can still shoot precision to a degree. Depending on the individual's skill level and the amount of slop in the mating of the upper to the lower could result in a clean "head shot" or a "whistle over the shoulder," as my dad always liked to say, when shooting at distance. But for the average shooter who doesn't normally shoot past 100-150 yards, center mass should be achievable no matter the fitment. All in all, I'm just saying that whether loose fitment is an issue is dependent on your usage and application of the tool itself. Just my opinion. </div></div>And it's nothing more than opinion, because it's not only incorrect, it also has absolutely no basis in fact.
Matched upper/lower sets are tourist traps. It they are too tight they will gall. Otherwise it doesn't matter.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BigtimeAub</div><div class="ubbcode-body">I would agree only to the point that loose doesn't matter as long as you're not concerned with precision shooting. I realize that precision shooting isn't necessarily on the minds of most of those whom are running the AR platform but you can still shoot precision to a degree. Depending on the individual's skill level and the amount of slop in the mating of the upper to the lower could result in a clean "head shot" or a "whistle over the shoulder," as my dad always liked to say, when shooting at distance. But for the average shooter who doesn't normally shoot past 100-150 yards, center mass should be achievable no matter the fitment. All in all, I'm just saying that whether loose fitment is an issue is dependent on your usage and application of the tool itself. Just my opinion. </div></div>And it's nothing more than opinion, because it's not only incorrect, it also has absolutely no basis in fact.
Matched upper/lower sets are tourist traps. It they are too tight they will gall. Otherwise it doesn't matter.
Re: uppers and lowers
No disrespect to any opinions offered so far, but I'll offer another opinion into the mix for what it's worth.
I've built a few lowers, built a few uppers, and have shot various match competitions in various formats for many years (tactical carbine, USPSA, 3-gun, NRA High Power Rifle, etc.). I can tell you that based upon my personal experience and observing others, matched uppers/lowers are NOT needed to achieve high levels of accuracy that will exceed the capabilities of most people (even top level shooters). I think some folks get caught up in the abstract and theory. Some benchrest shooters, and others, think you have to apply the same level of detail to all firearms...but that is simply not true or based in facts.
The bottom line is whatever makes you happy is all good, and it's your money to spend as you like. But in the world of AR's, matched uppers and lowers are not needed...a good quality upper, mated to a good quaility lower is all you need...YMMV
No disrespect to any opinions offered so far, but I'll offer another opinion into the mix for what it's worth.
I've built a few lowers, built a few uppers, and have shot various match competitions in various formats for many years (tactical carbine, USPSA, 3-gun, NRA High Power Rifle, etc.). I can tell you that based upon my personal experience and observing others, matched uppers/lowers are NOT needed to achieve high levels of accuracy that will exceed the capabilities of most people (even top level shooters). I think some folks get caught up in the abstract and theory. Some benchrest shooters, and others, think you have to apply the same level of detail to all firearms...but that is simply not true or based in facts.
The bottom line is whatever makes you happy is all good, and it's your money to spend as you like. But in the world of AR's, matched uppers and lowers are not needed...a good quality upper, mated to a good quaility lower is all you need...YMMV
Re: uppers and lowers
sounds good, thank you
sounds good, thank you
Re: uppers and lowers
My DPMS lower fits my PSA upper better than the PSA lower does. Still a good shooter though.
My DPMS lower fits my PSA upper better than the PSA lower does. Still a good shooter though.
Re: uppers and lowers
Most people you will talk to will say it doesn't matter about the fit being loose, but in my opinion the tighter the better. Just like any other rifle... It just makes sense to me. Never bought or built one that wasn't tight, and wouldn't buy or build one that wasn't.
Most people you will talk to will say it doesn't matter about the fit being loose, but in my opinion the tighter the better. Just like any other rifle... It just makes sense to me. Never bought or built one that wasn't tight, and wouldn't buy or build one that wasn't.
