This will be the THIRD time this data is posted, I don't give a whoot about the politics of the thing....this data should be publicly posted for the community!
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Starting from scratch AGAIN so fellow tinker-ers don't have to wade through the same mud we've been neck deep in...
What we Know
-The bolt was oversped by design to accomodate full auto fire (Atchison/Ceiner patent *Link needed*)
-A ball detent can be used to delay blowback and de-bounce the bolt, it is succesful but never took a foothold (lots of info on other forums)
-In a straight blowback gun the spring contributes nothing ("The machine gun" Chinn vol-4 pg. 15)
-Bolt speed should be <10m/s (Chinn again)
-Matching the 10/22 bolt weight is a good jumping off point (anecdotal knowledge)
-A buffer ALONE is a patch not a solution (catching skydiver in swimming pool)
-magnets are seldom the answer (outlined in another thread)
-A true conversion behaves different than a dedicated .22 upper (2 impulses, detonation&gas tube return pulse) but can be tamed in much the same way.
-43g is sort of a one size fits all number but errs on the low end to keep the gun reliable
-49g will get us reliable cycling with ammo from 40gr@1060 all the way up to the SSS with all its peculiarities.
-A TRUE Dynamic ABW (ricochets around) can be too heavy/light, or too long/short and the tuning parameters make it tricky to pin down a good match for each of our rifles (running with the 5 gal bucket of water vs a cup)
Colhogan was nice enough to do a heap of testing with his weight system and post all the results in m/s so we're all on the same unit measurement
(but you'll have to convert oz to grams for the weights.....Why? because all science is metric! HERE is a handy conversion tool)
Some of those numbers look slow at first glance but aguila's more exotic products use a slower burning powder that would seem to benefit from more time in the chamber (this is evidenced in the following test series videos)
(The blue gun is a .223 white oaks match upper 26" barrel.With a Cmmg "India" evo kit)
Initial tests 40gr@1060 and SSS with and without a 48gr weight
Followup tests 2x 40gr@1060 & 2x 40gr@1250 with the weights outlined in title
All details outlined in video
So now we have strong jumping off point on a variety of cartridges with a variety of weights.
Armed with this data and access to the weights you should be able to start to tune your specific setup for max performance. As you do, Post it all so we can build a database of what works best! Like the 50@200 thread over in the longrange forum we'll assemble a definitive data set that can act as a resource for all the newcomers.
+Hopefully the 10/22 benchrest guys are on to something and slowing the bolt down adds accuracy!?
Keep it civil, keep it on subject, post your experiences.
Be sure to include your setup, ammo used and the weight (in grams) added to the bolt.
(MODS,
IF THIS THREAD IS DELETED, I WOULD LIKE A REASON!!!
LeShaghal)
--------------------------------------------------------------------
Starting from scratch AGAIN so fellow tinker-ers don't have to wade through the same mud we've been neck deep in...
What we Know
-The bolt was oversped by design to accomodate full auto fire (Atchison/Ceiner patent *Link needed*)
-A ball detent can be used to delay blowback and de-bounce the bolt, it is succesful but never took a foothold (lots of info on other forums)
-In a straight blowback gun the spring contributes nothing ("The machine gun" Chinn vol-4 pg. 15)
-Bolt speed should be <10m/s (Chinn again)
-Matching the 10/22 bolt weight is a good jumping off point (anecdotal knowledge)
-A buffer ALONE is a patch not a solution (catching skydiver in swimming pool)
-magnets are seldom the answer (outlined in another thread)
-A true conversion behaves different than a dedicated .22 upper (2 impulses, detonation&gas tube return pulse) but can be tamed in much the same way.
-43g is sort of a one size fits all number but errs on the low end to keep the gun reliable
-49g will get us reliable cycling with ammo from 40gr@1060 all the way up to the SSS with all its peculiarities.
-A TRUE Dynamic ABW (ricochets around) can be too heavy/light, or too long/short and the tuning parameters make it tricky to pin down a good match for each of our rifles (running with the 5 gal bucket of water vs a cup)
Colhogan was nice enough to do a heap of testing with his weight system and post all the results in m/s so we're all on the same unit measurement
(but you'll have to convert oz to grams for the weights.....Why? because all science is metric! HERE is a handy conversion tool)
Some of those numbers look slow at first glance but aguila's more exotic products use a slower burning powder that would seem to benefit from more time in the chamber (this is evidenced in the following test series videos)
(The blue gun is a .223 white oaks match upper 26" barrel.With a Cmmg "India" evo kit)
Initial tests 40gr@1060 and SSS with and without a 48gr weight
Followup tests 2x 40gr@1060 & 2x 40gr@1250 with the weights outlined in title
All details outlined in video
So now we have strong jumping off point on a variety of cartridges with a variety of weights.
Armed with this data and access to the weights you should be able to start to tune your specific setup for max performance. As you do, Post it all so we can build a database of what works best! Like the 50@200 thread over in the longrange forum we'll assemble a definitive data set that can act as a resource for all the newcomers.
+Hopefully the 10/22 benchrest guys are on to something and slowing the bolt down adds accuracy!?
Keep it civil, keep it on subject, post your experiences.
Be sure to include your setup, ammo used and the weight (in grams) added to the bolt.
(MODS,
IF THIS THREAD IS DELETED, I WOULD LIKE A REASON!!!
LeShaghal)