I see those that build and sell 6AR ,6 ARC, ect.list using STIFFER uppers, and I'm wondering if this is just a selling ploy, since there are so many DIY 6 and 6.5 Grindle size case AR's built from a varied selection of uppers
Stiffer uppers ?
- Thread starter Baddog 0302
- Start date
I am not sure what a stiffer upper is but in terms of rigid uppers there is LMT MRP/MLC uppers and then everyone else.
Considering the amount of guns using regular two piece uppers that shoot lights out, I am not sure this matters practically speaking. Spend money on a good cut rifled barrel.
Considering the amount of guns using regular two piece uppers that shoot lights out, I am not sure this matters practically speaking. Spend money on a good cut rifled barrel.
The caliber doesn't have anything to do with upper selection, it's the weight and contour of the barrel that will dictate whether or not you want to run a heavier upper.
Depends on how far and how much weight is away from the barrel extension. I had a 224V with a heavy 24” and a 6” suppressor on a standard forged wilson upper. When the rifle was supported by the bipod, it wasn’t an issue. Once the weight was no longer supported, I was seeing a consistent 0.6mil drop in elevation on my dope across all ranges.
I put the upper in a vice and applied little pressure to the end of the muzzle and you can see the receiver extension flex. It’s simple, just like a crane, the further the weight is away from the base, the more it takes to maintain that load as it extends.
I put the upper in a vice and applied little pressure to the end of the muzzle and you can see the receiver extension flex. It’s simple, just like a crane, the further the weight is away from the base, the more it takes to maintain that load as it extends.
for example:
Noveske Gen III
BCM Mk2
Neat,
From an academic standpoint these look cool, It would be interesting to see a dispersion test between, this, the MRP, and a traditional upper with the same match grade barrel.
Hi,
But guess what those "stiff" uppers and the "limp noodle" uppers have in common that would lend itself to them "flexing" in a pretty similar fashion?????
They all use the same mounting/pivot pin holes.
Someone have the dynamic FEA showing the stiff upper flexes less at the mounting/pivot pin holes??
Sincerely,
Theis
But guess what those "stiff" uppers and the "limp noodle" uppers have in common that would lend itself to them "flexing" in a pretty similar fashion?????
They all use the same mounting/pivot pin holes.
Someone have the dynamic FEA showing the stiff upper flexes less at the mounting/pivot pin holes??
Sincerely,
Theis
Yeah, I think this is mostly academic/theoretical
Thank you all for your thoughts on my question regarding "stiff" / "ridge" uppers. An internet search showed that all those listed are "out of stock". So my plan is to try and pick up an AR that some "zombie killer" {clay pit shooting at 25 -30 Yds} and now can't find / afford ammo and needs $$ for something else.
I think the "flex" thing wouldn't be a problem as I plan to go with no more that a 20" Bbl. and always shoot from a bench using either a bi pod or front and rear rests .
I think the "flex" thing wouldn't be a problem as I plan to go with no more that a 20" Bbl. and always shoot from a bench using either a bi pod or front and rear rests .
Conceptually I like the idea of increasing upper stiffness. But, the Noveske and BCM receivers are thickened in ways that shouldn't really matter.
To me, it appears the least stiff area is the threaded extension. The area behind that is considerable taller/wider and should be much more stuff. So, I would look for receivers and handguards that use non-standard attachments with increased thickness in the classically threaded area. Examples of this would be the Larue and Aero Enhanced models.
To me, it appears the least stiff area is the threaded extension. The area behind that is considerable taller/wider and should be much more stuff. So, I would look for receivers and handguards that use non-standard attachments with increased thickness in the classically threaded area. Examples of this would be the Larue and Aero Enhanced models.
I'd suggest you review your technique.
How did you rest your rifle when not using the bipod?
There are other dynamics involved in positional shooting that can result in shifting POI.
Another claimed advantage is that there is less stress on bolt lugs due to the barrel extension remaining better aligned with the bolt during cycling. It would be interesting to see an actual test for bolt durability with a normal M4 upper, a Colt Le6944 and something like a BCM Mk2 with all other variables held equal.
Something like the monolithic Colt or LMT MRP is probably going to be much more rigid as they redesigned the barrel nut as well, rather than just stiffening the upper around the ejection port.
Something like the monolithic Colt or LMT MRP is probably going to be much more rigid as they redesigned the barrel nut as well, rather than just stiffening the upper around the ejection port.
It doesn't take the integral f(x) by separation of parts to understand that your solution set is i.
Sand box is over there.
And you didn't even have to simplify the exponent of epsilon for the
integrating factor, sir.
The Noveske Gen III is self righteous in form. The algebraic solution to fulcrum problems
is BB problems for BB brains. Back in '75-'76, Micah Chan made university mathematics fun and easy.
Sabreco, Inc. used to give classes/info [during a phone call] on why thicc uppers are required for the 6mm AR cartridges.
Best to all.
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on why thicc uppers are required for the 6mm AR cartridges. Care to explain what you or "they"meant by this ?
At the end of the day your still hanging a heavy piece of steel from an aluminum receiver. It has limits.
Not sure if that's the selling point of these one piece units, But as 357 Max says there is only one point of contact for the barrel and the upper. And like "bolt guns" you would loose the "free floating barrel" if there was any support built in or added to the hand guard
I had a JP handguard on an Aero M5 standard upper with a .308 JP barrel. It was not forgiving in regards to loading the bipod at varying amounts. Was getting misses on small targets at 500+ yards depending on my preload weight.
Switched over to a Aero M5 enhanced with same barrel, found it much more forgiving. I can load as much or little now and don't notice a difference down range.
Out of curiosity I jammed my finger between the handguard and barrel while preloading the bipod. Old setup would pinch my fingers with slight pressure, the M5 enhanced setup did not give the same hard pinch.
Switched over to a Aero M5 enhanced with same barrel, found it much more forgiving. I can load as much or little now and don't notice a difference down range.
Out of curiosity I jammed my finger between the handguard and barrel while preloading the bipod. Old setup would pinch my fingers with slight pressure, the M5 enhanced setup did not give the same hard pinch.
