PhantomVOZ
Elite
I have been thinking of placing the SA-16A2 upper on a lower with a carbine buttstock. What would be the best buffer weight to use?
Which buffer weight suits a 20 inch rifler upper?
- Thread starter PhantomVOZ
- Start date
Bassbob
Emissary
AR15 Sprinco Enhanced Power Carbine Spring (Blue) W/ KAK H2 Buffer (4.7oz)
AR15 Sprinco Enhanced Power Carbine Spring (Blue) W/ KAK H2 Buffer (4.7oz)
bkingsfirearms.com
TEXASforLIFE
SAINT
if it's like most military rifles, they are overgassed and would need (in most cases) what @Bassbob posted, but it's more of a full or select fire buffer weight. not knowing what SA has used for this gun it's difficult to say if it's overgassed or not? more weight you have on the bcg and behind it you will have more felt recoil! for the non-adjustable gas blocks buffer weight (not knowing what testing of brands and weights of bullets) can be a mix and match to what you need for reliability. also take note of this...........when changing from rifle to carbine, parts need to be compatible (milspec vs commercial). it's not a length or inside diameter (buffer tubes), but a diameter compatibility with stocks and tubes as not to wobble or be too tight. in most cases a standard weight spring and 3.25-3.5ish oz buffer suffices.
Talyn
SAINT
I use a either a Spikes Tactical T2 or T3. Either works fine.
Also, you don't need any fancy recoil spring. I only use the Brownells "standard" weight spring but the chrome-silicon ones for extra life in my A5s.
TEXASforLIFE
SAINT
A5's use a rifle length spring and requires an A5 buffer tube incase the op doesn't know? It also requires a 3.995" A5 buffer for the carbine.
Talyn
SAINT
Negative.
The A5 was never "formalized" as a mil-configuration, but is commonly used to describe a 20" A2 or A4 modified with a collapsible stock, buffer tube & spring.
VLTOR developed a A5 proprietary system which one can use if they want to spend the $$ but its unnecessary since the carbine buffer tube, spring and any collapsible stock, works perfectly well.
The VLTOR AR buffer tube is only 3/4" longer than a carbine tube in order for one to use a riffle-length buffer, but neither is needed since a carbine tube with a T2 or T3 buffer works just fine. The VLTOR A5 system is just a marketing scheme.
The Canadians have been using a standard carbine buffer tube & spring for years. As well, the USMC and US Army approved a field upgrade kit using the same.
There is no need for the VTOR A5 parts unless you want to use them since a A2 and A4 function perfectly fine with a carbine buffer tube, appropriate buffer & recoil spring.
I described all that in these threads.
www.thearmorylife.com
www.thearmorylife.com
Plus
www.kommandoblog.com
M16A4 with collapsible stock.
The A5 was never "formalized" as a mil-configuration, but is commonly used to describe a 20" A2 or A4 modified with a collapsible stock, buffer tube & spring.
VLTOR developed a A5 proprietary system which one can use if they want to spend the $$ but its unnecessary since the carbine buffer tube, spring and any collapsible stock, works perfectly well.
The VLTOR AR buffer tube is only 3/4" longer than a carbine tube in order for one to use a riffle-length buffer, but neither is needed since a carbine tube with a T2 or T3 buffer works just fine. The VLTOR A5 system is just a marketing scheme.
The Canadians have been using a standard carbine buffer tube & spring for years. As well, the USMC and US Army approved a field upgrade kit using the same.
There is no need for the VTOR A5 parts unless you want to use them since a A2 and A4 function perfectly fine with a carbine buffer tube, appropriate buffer & recoil spring.
I described all that in these threads.
The M16/AR-15A5 Concept Rifle
A Builder’s Guide to the M16A5 Concept Rifle. There was/has never been an official designation of the M16A5 rifle. The image in the cover of this very article is actually the Canadian C7A2. This configuration is extremely shootable. It’s one of my favorite rifles in the safe and works very well...
www.thearmorylife.com
A Builder’s Guide to the M16A5 Concept Rifle
I've done this on several 20" ers with a standard CTR stock, carbine spring and T2 buffer and they run fine and smooth. https://www.everydaymarksman.co/equipment/m16a5/
www.thearmorylife.com
Plus
The USMC M16A5 Concept: History and Build - The Kommando Blog
Prior to the M4 and M27 takeover, the USMC briefly considered a path that would have extended the life of Gene Stoner's 20" full size rifle series.
www.kommandoblog.com
M16A4 with collapsible stock.
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TEXASforLIFE
SAINT
so, what part of A5 is wrong on my part as it does contain the correct info. B5 on the other hand is just furniture
TEXASforLIFE
SAINT
so your reference of A5 isn't about vltor on the A and number change after the letter (as in A1, A2, A3 and so on)
Talyn
SAINT
Shorter length M16/AR15 barrels are over-gassed due to the gas port being closer to the chamber vs. the original 20" length for which the 5.56 was designed for.
Chart of barrel length against bore pressure.
TEXASforLIFE
SAINT
i don't believe exit/muzzle pressure would be that low, especially on a small bore and chamber pressure @ 55-60k. 17k @ 7".......no way unless it's a sub round then maybe
Talyn
SAINT
That's the pressure(s) once the bullet exists the barrel with mil-spec loads.
Pressure goes down with greater barrel volume as the chart indicates.
TEXASforLIFE
SAINT
i realize that, but no way it's that low or concussion from pressure would be less........ask @10mmLife about his experience with a shorter barrel. unless powder has changed (which could happen as it can change exit pressures) to keep velocity the same, there's still no way for it to be that low. i'll try and do some reloading on those projectiles and chrono them, but don't have a 14.5 or 7" barrel. hopefully quick load will help out as it takes many tweaks/adjustments to perform correctly. chrono info is a start and much needed for ql adjustments.
TEXASforLIFE
SAINT
i would like to have a pressure trace to more accurately verify, but not knowing the exact powder used keeps me from inputting it into ql. the newer powders for mil ammo aren't available like the old days where it was just imr with a different designation. faster burning powders might yield close to listed velocity and will produce less muzzle pressure as it will burn off faster closer to the chamber unlike slower powders. you reload and know about this. probably been reloading longer than me and a lot more as you did prs and/or competition shooting. ql give pressure numbers the whole length of the barrel inputted all the way to the muzzle and if enough of the info put into ql it can give numbers that are within a smaller variance. with others that use ql that will state a chrono is needed to verify as you might need to change values. knowing case volume (h2o) is of big importance along with muzzle numbers. after that you can tweak to meet chrono results. having m855 and m/xm193 i can get a start if i get chrono numbers from barrels i have. i'll also check velocities between other barrels of the same length to get a more well-rounded test. if you need or want some more 140gd's midsouth has some for a good price?