- Thread starter Dildobaggins
- Start date
Barrel to upper fitment can have a huge effect if it is especially bad.
Metallurgy.
A forged and machined lower will have a different array of internal metallic crystal arrangement as opposed to a lower machined from a rolled billet.
Beware cast lowers.
There are only a few suitable alloys that can be cast without jeopardizing strength and abrasion resistance.. Yes, you can investment cast a perfectly good looking lower, complete with lots of features already in place. "Cold forming" after casting can square things up nicely.
HOWEVER, it is virtually impossible to cast a lower in 7075 or even 6061, even using vacuum displacement methods. as used for Titanium. There ARE some pretty good casting alloys, BUT they are NOT on the "Mil Spec for AR lowers.
Additionally, even the better casting alloys have "issues" with Hard Anodizing.
If you go down the "machined from billet" road, it would be wise to chose a design that has a bit of extra "beef" around stress points like hinge-pin holes, the mag well and the rear where the buffer tube is fitted.
SOME manufacturers have been doing this for a LONG time, purely for the civilian market. I vaguely recall an AR brand called "The Edge" many years ago, They made a FEATURE out of their machined receivers with extra reinforcing bits on the outside.
Bear in mind that as a civilian user you are unlikely to be launching grenades, conducting CQB in dusty, gritty places for days on end, or bayoneting or butt-stroking opponents.
In the latter scenarios, if your rifle breaks, you can be fairly certain there will be others, very like it, lying around, ready to go.
A forged and machined lower will have a different array of internal metallic crystal arrangement as opposed to a lower machined from a rolled billet.
Beware cast lowers.
There are only a few suitable alloys that can be cast without jeopardizing strength and abrasion resistance.. Yes, you can investment cast a perfectly good looking lower, complete with lots of features already in place. "Cold forming" after casting can square things up nicely.
HOWEVER, it is virtually impossible to cast a lower in 7075 or even 6061, even using vacuum displacement methods. as used for Titanium. There ARE some pretty good casting alloys, BUT they are NOT on the "Mil Spec for AR lowers.
Additionally, even the better casting alloys have "issues" with Hard Anodizing.
If you go down the "machined from billet" road, it would be wise to chose a design that has a bit of extra "beef" around stress points like hinge-pin holes, the mag well and the rear where the buffer tube is fitted.
SOME manufacturers have been doing this for a LONG time, purely for the civilian market. I vaguely recall an AR brand called "The Edge" many years ago, They made a FEATURE out of their machined receivers with extra reinforcing bits on the outside.
Bear in mind that as a civilian user you are unlikely to be launching grenades, conducting CQB in dusty, gritty places for days on end, or bayoneting or butt-stroking opponents.
In the latter scenarios, if your rifle breaks, you can be fairly certain there will be others, very like it, lying around, ready to go.
Interesting, the arrow o have and have shot all feel very tight with. It alot of wiggle of any between lower and upper receiver. Can comment on finish cause I've never held anything higher than a BCM
Man I remember 10-11 years ago when dudes were buying plum crazy lowers for shits and giggles just to try and build ultralight rifles... everyone was just having fun.
Now we all gotta be Delta meal team six Ranger seal pups.
At the risk of sounding poor or "just as good" just run what makes you happy. I personally won't run a KAC lower. When the day comes I am ready to do a true precision gas gun I'll probably just buy something from JP or Seekins. For now my black Friday LaRue barrel in an Aero M4E1 is plenty accurate.
Now we all gotta be Delta meal team six Ranger seal pups.
At the risk of sounding poor or "just as good" just run what makes you happy. I personally won't run a KAC lower. When the day comes I am ready to do a true precision gas gun I'll probably just buy something from JP or Seekins. For now my black Friday LaRue barrel in an Aero M4E1 is plenty accurate.
i am operator af, and even my air rifle costs thousands of dollars.
and i am a poor.
While overseas, how many of those stress points did you see go down?
You should be good with a quality lower like Aero, the big thing that helps with accuracy is triggers, barrels, uppers, and etc. The lower based off price really does nothing much than you’ll be able to use maybe better accessories with some better brands, the finish might be better, and more durable but as far as accuracy the lower really doesn’t have any bearing on accuracy.
If a lower is made of the same material and machined, finished to MilSpec, the name is merely a status symbol. They charge what the market will bear. It's called free enterprise capitalism. What made America GREAT, long before Trumpy. The root of the old adage, "A fool and their money are soon parted." I have numerous cheapo lowers/uppers. Run them hard without issue. That said, I also have many more Barrett, LMT, DD, Noveske, Colt, Knights, et el. All more expensive, more status among friends. One evaluates the offerings, makes their choice,pays their money, has their own experiences.
I've own(ed) Aero, Spikes, KAC, LMT, DPMS, Colt, and Sendra lowers. None of them gave me any reliability issues.
The oldest that I still have is a Spikes that has been in use for 13 years in all kinds of conditions and has over 5K rounds on it. One of the Spikes that I bought at the same time had extension threads that were on the tight side and I could not get an extension to screw into it. Spikes replaced it for free.
The magwell on the LMT MARS-L that I had was super tight. You could barely get a PMAG into it without slamming it home and it wouldn't drop free. GI and Lancer mags worked fine but I ended up trading it off. If they fix the magwell issue then I may pick up another as I liked the ambi features.
I like KAC stuff, and am happy with my ambi lower, but there is a price to be paid for quality.
The oldest that I still have is a Spikes that has been in use for 13 years in all kinds of conditions and has over 5K rounds on it. One of the Spikes that I bought at the same time had extension threads that were on the tight side and I could not get an extension to screw into it. Spikes replaced it for free.
The magwell on the LMT MARS-L that I had was super tight. You could barely get a PMAG into it without slamming it home and it wouldn't drop free. GI and Lancer mags worked fine but I ended up trading it off. If they fix the magwell issue then I may pick up another as I liked the ambi features.
I like KAC stuff, and am happy with my ambi lower, but there is a price to be paid for quality.
I will try to answer your questions, but I am not an expert. I have built well in excess of 70 lowers and stripped and rebuilt more. I am assuming we are only discussing stripped lower receivers.
If you have a need or a desire for ambi controls, than there are certain lowers that are more conducive to ambi controls. Once again, assuming we are talking about the current KAC stripped lower, they have additional machining to accommodate ambi controls. A google search for KAC lower issues will result in many issues they had with their stripped lowers in the past, but it was a different lower. Hence, you are paying a bit more for the additional machining, QC and finishing. Perhaps a bit for the name. So, if ambi is important and/or the name is important, then perhaps, it may be worth the additional cost.
I can't guess what you mean by different stripped lowers and higher pedestal. I can give my personal experience. Prior to beginning a build, I take various measurements of the stripped lower. I inspect it for obvious defects. (such as the grip not being completely tapped and the bolt catch recess being short drilled and or tapered etc.) If the receiver appears to be free of obvious defects and the measurements being in spec, I will begin test fitting parts and inspecting for burrs etc. This includes test fitting uppers and pins and magazines etc.
My understanding is that some lowers are a bit more expensive due to better QC and or the finishing package the manufacturer decides upon. I have seen various lowers that appear to be better machined than others. I have come across a few lowers that were definitely out of spec, including one from a "top tier" company.
Something else I have noticed is that on certain lowers from companies that charge a bit more, is that the dimensions are more consistent. I am guessing this is due to their demands on the actual finish package requests and QC. The only issue may be in tolerance stacking. Hence, a cheaper lower that has dimensions that are in spec, but at the minimum or max may cause some issues with parts that are at the opposite end of the in spec dimension. I am not saying that it will cause an issue, just something to keep in mind.
Hence, some companies do a better job with finish and QC and you pay a bit more. The Aero lowers I have seen have all been in spec and nice. So, I hope this helps, but I am not an expert nor play one on TV.
Cheers, Steve
Forgive my ignorance if I'm wrong here, as I've kind of been out of the game for a bit, but aren't all forged lowers made at the same handful of places? I'm sure there is final machining that's completed after that. But if the handful of places is still correct then I would guess most forged lowers are "roughly" the same quality. Billet lowers are a whole difference ball game.
I've heard similar about the forgings. Machining and anodizing are anomalies based on the final seller.
Buy brand names for cheap like blemish or overruns or on sale.
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Don't ask that or say that on ARF com... or any facebook AR group. Them words trigger the tactibros.
And whatever you do do not ever use the word potmetal without a pre-emptive "kiss my ass".
