SwissyJim
17 June 2016, 19:30
Ok, fun day at the range. Poor guy sharing my banks of shooting lanes with his College level competition air rifle (ANSCHÜTZ, I think?) had to put up with my SBR unsuppressed (mostly ). But I didn't want to clutter up Molon's thread on the Hornady TAP SBR any more than we did. But there was discussion about the Hornady TAP SBR ammo and how it would run differently in a SBR - all Molon had to test with was a 14½" barrel and supposedly the TAP SBR is designed for 10½-12" barrels.
Anyways... interesting data. I did NOT do anything for accuracy as Molon can and does do a MUCH better job than I ever could. But, with my magnetospeed chrony I was able to get some good info. I ended up testing a number of different loads:
[B]Winchester 5.56 55gr FMJ (bulk white box)
Series, 1, Shots:, 5
Min,2660, Max,2794
Avg,2739 ,S-D,51.7
ES , 134
Series,Shot,Speed
1, 1, 2660, ft/s
1, 2, 2775, ft/s
1, 3, 2727, ft/s
1, 4, 2794, ft/s
1, 5, 2741, ft/s
my plinking reloads - CFE223 powder with Hornady 55gr FMJ
Series, 2, Shots:, 5
Min,2190, Max,2313
Avg,2220 ,S-D,51.8
ES , 123
Series,Shot,Speed
2, 1, 2313, ft/s
2, 2, 2200, ft/s
2, 3, 2195, ft/s
2, 4, 2190, ft/s
2, 5, 2206, ft/s
PMC 223 55gr FMJ
Series, 3, Shots:, 5
Min,2322, Max,2433
Avg,2369 ,S-D,55.9
ES , 111
Series,Shot,Speed
3, 1, 2427, ft/s
3, 2, 2340, ft/s
3, 3, 2324, ft/s
3, 4, 2322, ft/s
3, 5, 2433, ft/s
Black Hills 5.56 77gr OTM
Series, 4, Shots:, 5
Min,2318, Max,2374
Avg,2346 ,S-D,22.8
ES , 56
Series,Shot,Speed
4, 1, 2318, ft/s
4, 2, 2374, ft/s
4, 3, 2353, ft/s
4, 4, 2328, ft/s
4, 5, 2358, ft/s
Hornady TAP 223 75gr
Series, 5, Shots:, 5
Min,2243, Max,2273
Avg,2259 ,S-D,14.7
ES , 30
Series,Shot,Speed
5, 1, 2243, ft/s
5, 2, 2268, ft/s
5, 3, 2273, ft/s
5, 4, 2270, ft/s
5, 5, 2244, ft/s
Hornady TAP 5.56 SBR 75gr
Series, 6, Shots:, 5
Min,2170, Max,2188
Avg,2178 ,S-D, 7.4
ES , 18
Series,Shot,Speed
6, 1, 2184, ft/s
6, 2, 2179, ft/s
6, 3, 2170, ft/s
6, 4, 2173, ft/s
6, 5, 2188, ft/s
I was a little surprised at the TAP SBR... I thought it was gonna be faster. But, it is a 75gr bullet and what surprised me more was the data... the SD and ES numbers are outstanding... the consistency was extremely good. I need to work on my reloads to get my numbers down, but in my defense they are just a 'steel plate at the range' plinking round (100yrd). Thi sfall maybe I'll see how it does in the home made gel...
alamo5000
17 June 2016, 20:08
Interesting that the TAP .223 and the Black Hills ammo were both faster at the same weight.
I thought the point of the SBR load was to be faster out of a shorter barrel. Did I miss something?
I am not so sure if that is the entire story here or not. The idea is for fragmentation or expansion. The bullet design on the SBR load is a blunt nosed soft point. I will speculate but it could be that too much velocity with that type of bullet would cause the bullet to shatter and not really penetrate as much.
I really have no idea so I am just giving it a SWAG.
Here is the description from Hornaday:
TAP® SBR™ is designed specifically for 10.5"-11.5" SBR’s by using proprietary propellant technology and a bullet designed with technology from industry leading Critical Duty® FlexLock® bullets. TAP® SBR™ provides exceptional ammunition performance in SBR’s suppressed or unsuppressed, with virtually no flash or residue, dramatically reduced sound signature, will not foul or overheat suppressors, uniform velocity and accuracy, and provides controllable rate of fire in automatic platforms. Designed to meet the requirements of the FBI protocol, TAP® SBR™ is the optimum choice for 10.5"-11.5" barreled 5.56 rifles.
The flexlock is supposed to have a tougher core but has the ability to penetrate barriers while still expanding...
The rest of it is pretty much summed up in the second underlined sentence.
It would be interesting to see a sound test with it to see if it's any better. If you recall I tried doing an experiment on reducing sound signature by choosing a different powder and I wasn't very successful (but I learned a lot)....
BoilerUp
18 June 2016, 13:47
Oh I got it now. So it's bullet based performance rather than velocity based performance. More or less.
I hadn't really dug into it as I don't own an SBR.
I'd say they're related. Terminal performance, especially expansion, is dependent on velocity, but not all bullet designs behave the same way. My read of the TAP SBR round is that the bullet will have acceptable terminal performance for the velocities to which it is loadad. The velocities are lower, I suspect, because they are using a faster burning powder that will be consumed within 10" or so, which sacrifices a bit of velocity, all for the reasons that Alamo quoted above.
SwissyJim
18 June 2016, 15:02
I can't comment on the noise factor, as I have no fancy gear for that other than my hear impaired ears. But I can say that suppressed they did not smoke much, SEEMED quieter, and I wish I had peeked down the barrel afterwards to see if there was any unburnt powder - I've seen some with certain other loads. Next time I take them out I'll try that. I won't be able to gel test anything till fall, since my homemade gel is a little temp sensitive (ie starts melting). I honestly thought I'd get better FPS from the SBR stuff, even with faster powder, but more efficient burn and terminal ballistics is more important to me. I may pull one apart and see what the charge weight is but at a buck a pop I may not LOL
BoilerUp
25 June 2016, 07:38
Anybody got a Tap-SBR clone yet ? Iv'e got 6k of 55gr coming tomorrow and these will all be run through a 10.5 in barrel .
Basically a 55gr bullet in almost any format (barring they can come up with some copper expanding $1 a bullet magic solution) isn't good for SD purposes out of an SBR. There is simply not enough velocity for those particular bullet designs for them to function as designed.
Alamo, I think Sak007 is looking for load data that mimics the Hornady TAP round. The main difference here is, I believe, that Hornady is using a faster burning powder than normal. A little bit of internet trolling suggests the propellant used by Hornady for this round isn't available to reloaders.
Regarding 55gr bullets, the Barnes TSX 55gr and Speer Gold Dot 55gr should give you good expansion out of an 8"-10.5" barrel at HD ranges. Plinking w/ cheap 55gr FMJ will likely give you a very close POI to the HD rounds, too, but always verify zero on your HD weapon with the rounds you intend to use in a HD role.
Personally, any weapon that I'd even consider reaching for in a HD situation has a few mags of either Gold Dot or Barnes TSX loaded up (factory loads).
FWIW, PSA has been selling the GD for $10/box lately. Stock up.
alamo5000
25 June 2016, 07:53
Alamo, I think Sak007 is looking for load data that mimics the Hornady TAP round. The main difference here is, I believe, that Hornady is using a faster burning powder than normal. A little bit of internet trolling suggests the propellant used by Hornady for this round isn't available to reloaders.
Regarding 55gr bullets, the Barnes TSX 55gr and Speer Gold Dot 55gr should give you good expansion out of an 8"-10.5" barrel at HD ranges. Plinking w/ cheap 55gr FMJ will likely give you a very close POI to the HD rounds, too, but always verify zero on your HD weapon with the rounds you intend to use in a HD role.
Personally, any weapon that I'd even consider reaching for in a HD situation has a few mags of either Gold Dot or Barnes TSX loaded up (factory loads).
FWIW, PSA has been selling the GD for $10/box lately. Stock up.
For sure. Those Barnes bullets would work like a charm I think although I have exactly zero experience with them. For a buck fifty a round it could be an option. I hear nothing but stellar reviews of all the grain weights with those.
My propensity is to lean to a heavier bullet myself but the 55gr plinker rounds are super cheap.
As for matching the TAP load if you are reloading I don't think it will be a challenge at all to match the velocities. I had a bunch of notes that I packed away before my trip showing my chronographed velocities using 75 and 77 grain bullets but I don't know where those notes are. l have a box of 75 gr that needs to be tested out still but in my opinion just getting to those velocities is not a problem at all for an average reloader but so far the 75gr seems like my go to choice for the price/benefit ratio. I will let you know what load I come up with.
For me my likelihood of shooting anyone with an SBR is pretty low but my likelihood of shooting a few pigs with one is pretty damn high.
BoilerUp
25 June 2016, 08:08
As for matching the TAP load if you are reloading I don't think it will be a challenge at all to match the velocities.
I only use the Barnes for my 300 BLK as that caliber generally has shitty terminal ballistics out of any other round. Gold Dot for .223, 9mm and 6.8 SPC. But, yeah, I went with the 64gr for the .223.
I think you're missing the point of the TAP SBR round. It's not about velocity. It's about not being a flame thrower. The velocities out of the round are actually kind of anemic, making it only a 75-100 yard round (if you want effective terminal ballistics) but the trade off is worth to some, in certain situations. Like, if you shoot people inside houses in the dark.
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