GUN best ammo for sps tactical 1:9 twist?

Discussion in 'On Topic' started by thegooch, Nov 12, 2009.

  1. thegooch

    thegooch OT Supporter

    Joined:
    Jan 5, 2008
    Messages:
    15,580
    Likes Received:
    40
    This shit pretty good?

    [​IMG]
     
  2. vwpilot

    vwpilot New Member

    Joined:
    Jan 9, 2005
    Messages:
    1,596
    Likes Received:
    0
    Its ok stuff. I've used the .308 stuff and its about a 1 1/4 moa ammo out of my Savage which I can consistently shoot at sub MOA with something like Federal Gold Medal Match.

    I havent chrono'd it, but it seems like its just not consistent. Also point of aim is hugely different from the Federal. Like several inches different which means it was loaded a lot hotter than the muzzle velocity rating would have you to believe.

    Now that was with .308. I imagine if you like a good inexpensive plinking ammo, it would be great. That is what I feed the AR10 since its much less than the Federal and the AR is only a moa gun on a good day anyway.
     
  3. Cannondale

    Cannondale OT Supporter

    Joined:
    Apr 17, 2007
    Messages:
    83,763
    Likes Received:
    561
    Location:
    Austin, TX
    All the PPU stuff I've shot has been of high quality, but maybe not the utmost in consistency. I haven't ever bought the match stuff though, just like it because I can get boxer primed 7.62x54r and 7.5x55 Swiss from them.

    Federal match is what my dad uses and he's gotten about 1 M.O.A. with a box-stock Rem 700 sps in .30-06 with it.
     
  4. THT

    THT The easy way is always mined

    Joined:
    Mar 16, 2005
    Messages:
    12,748
    Likes Received:
    0
    Location:
    The booby hatch
    Hornady .223 75gr TAP is better.
     
  5. johnson

    johnson New Member

    Joined:
    Nov 21, 2003
    Messages:
    38,412
    Likes Received:
    0
    $20 a box vs $9. Hmm...
     
  6. He did ask for the best ammo. :dunno:
     
  7. johnson

    johnson New Member

    Joined:
    Nov 21, 2003
    Messages:
    38,412
    Likes Received:
    0
    Molon got good results with Prvi 75 gr Match.


    100 Yard Accuracy Evaluation of Prvi Partizan 75 grain Match Ammunition.

    [​IMG]



    The Prvi Partizan 75 grain match ammunition uses an open-tip-match bullet very similar in configuration to Hornady’s 75 grain BTHP bullet used in Hornady’s TAP line of ammunition and in Black Hills’ 75 grain MHP line of ammunition. The Prvi Partizan (PPU) bullet has a nominal length that runs approximately 0.010” – 0.015” shorter than the Hornady bullet. The PPU 75 grain bullet does not have a cannelure, but the case mouth on this load does have a slight collet crimp on it which puts a slight crease in the bullet.



    [​IMG]




    [​IMG]






    The PPU 75 grain match load uses Boxer primed brass cases and is charged with “ball” powder. Neither the primer nor the case mouth have sealant and the primer is not crimped. Previous chronographing of this load through multiple barrel lengths shows it to run an average of 127 fps slower than the Black Hills 75 grain MHP load.


    [​IMG]




    [​IMG]




    [​IMG]




    I have read some statements recently that claim the PPU 75 grain bullet was designed to shoot well through 1:9” twist barrels, yet none of those making these statements have provided any scientific evidence to support this claim. According to the Greenhill formula, the optimal twist for the PPU 75 grain bullet is 1:7.6”.

    From a 1:9” twist barrel, the PPU 75 grain match bullet has a gyroscopic stability factor (GSF) of less than 1.25 for all velocities. It is generally accepted that a rifle bullet should have a GSF of 1.5 to 2, with 1.25 being the least acceptable GSF.




    Gyroscopc stability factor from a 1:9" twist barrel.

    [​IMG]




    Gyroscopic stability factor from a 1:7.7" twist barrel.

    [​IMG]




    The test-vehicle for this evaluation was an AR-15 with a 24” stainless-steel Kreiger VarMatch barrel, with a 1:7.7” twist, installed on a LaRue Tactical Stealth upper receiver. A Leupold Competition Series Scope was used for sighting. No malfunctions of any kind were experienced during testing.




    [​IMG]




    Following my usual protocol for accuracy evaluation, shooting was done from a bench-rest at 100 yards. Three 10-shot groups were obtained using the PPU 75 grain match load. Those three groups had extreme spreads that measured:

    0.66”
    0.92”
    1.14”

    for an average extreme spread of 0.91”.



    The best 10-shot group from 100 yards.

    [​IMG]




    The three groups from above were overlayd on each other using RSI Shooting Lab to obtain a 30-shot composite group. The mean radius of this composite group was 0.29”. For comparison, this composite group is pictured below next to a composite group of the Black Hills 75 grain red box MHP load as well as a composite group of one of my handloads.



    [​IMG]






    Chronograph Data for Prvi Partizan 75 grain Match Ammunition


    [​IMG]


    Chronograph data was obtained using an Oehler 35-P with "proof screen" technology. All velocities listed are muzzle velocities as calculated from instrumental velocities using Oehler's Ballistic Explorer. All strings of fire consisted of 10 shots each.

    Three different barrel lengths were used in testing: 20", 16" and 14.5". All barrels were of Colt manufacture, with chrome lining, NATO chambers and 1:7" twists.


    [​IMG]




    atmospheric conditions:

    Average temperature- 83 degrees F
    Humidity - 64%
    Barometric pressure – 30.04
    Elevation- 960 feet above sea level




    Prvi Partizan 75 grain Match; Velocity Update


    Here's a little update on the velocity aspect of the PPU 75 grain Match load. One can't help but wonder if Prvi Partizan has been listening to its customers. About the only complaint anyone has had with this load is that it has a lower muzzle velocity than the Hornady or Black Hills 75 grain loads. I recently chronographed the latest lot of the PPU 75 grain Match load that I have on hand and from a 20" Colt A2 barrel it is running approximately 117 fps faster than the original lots of this ammo that I chronographed!


    [​IMG]
     
  8. johnson

    johnson New Member

    Joined:
    Nov 21, 2003
    Messages:
    38,412
    Likes Received:
    0
    $15.75 a box shipped for 20 boxes of Hornady #80265.
    http://www.gunbroker.com/Auction/ViewItem.asp?Item=146626889

    Hornady 75 grain 223 TAP LE versus 75 grain MATCH

    [​IMG]



    Hornady’s 75 grain BTHP Match ammunition (part #8026) is loaded with the same 75 grain boat-tail hollow point bullet that is available from Hornady as a reloading component (part #2279). The case mouth of the Match load has a slight taper crimp on it which puts a small crease in the bullet itself. The Hornady 75 grain 223 TAP load (part #80265) uses essentially the same 75 grain BTHP bullet as the Match load with the addition of a cannelure. Unfortunately, the cannelured version of this bullet is not generally available to the public as a reloading component.


    [​IMG]




    [​IMG]




    Previous lots of both the Match and 223 TAP load have been charged with a short-cut, charcoal colored extruded powder, while the most recent lots that I have purchased (including the ones used in this test session) are charged with a greenish/yellowish colored short cut, extruded powder resembling those powders found in the Hodgdon lineup of powders. Both loads use traditional brass cases and the caseheads from both loads are head-stamped “Hornady 223-REM” and neither load appears to have sealed nor crimped primers. The case mouth of the 223 TAP load is crimped into the cannelure of the bullet.




    [​IMG]




    [​IMG]




    previous powder
    [​IMG]




    recent powder
    [​IMG]




    Chronograph testing was done using an Oehler 35-P chronograph with "proof-screen" technology. All strings of fire consisted of 10-shots each. All velocities listed below are muzzle velocities, as calculated from the instrumental velocities using Oehler’s Ballistic Explorer software program.




    [​IMG]




    [​IMG]




    Accuracy testing was performed using my 24” Krieger barreled AR-15. Shooting was done from a bench-rest at 100 yards. All groups were 10-shot groups. Prior to testing the Hornady ammunition, I fired a 10-shot control group using handloaded 55 grain Sierra BlitzKings. That group had an extreme spread of 0.63”.




    [​IMG]





    Starting with the Hornady 75 grain 223 TAP load, I fired five, 10-shot groups from 100 yards and used the best three groups for analysis. Those three groups had extreme spreads that measured:

    1.17”
    0.87”
    1.05”

    for a 10-shot group grand average of 1.03”. The three 10-shot groups were over-layed on each other using RSI Shooting Lab to form a 30-shot composite group that had a composite mean radius of 0.32”.


    best 10-shot group of 75 grain 223 TAP

    [​IMG]





    In the same manner described above, I obtained three 10-shot groups of the Hornady 75 grain Match load. The extreme spreads of those groups measured:

    0.89”
    1.03”
    1.16”

    for a 10-shot group grand average of 1.03”! Over-laying those three groups on each other using RSI Shooting Lab yielded a 30-shot composite group with a mean radius of 0.36”.



    best 10-shot group of 75 grain MATCH

    [​IMG]




    For additional comparison, I obtained three 10-shot groups from 100 yards using hand-loaded Hornady 75 grain BTHP bullets. The extreme spreads of those groups measured:

    0.78”
    0.71”
    0.52”

    for a 10-shot grand average of 0.67”. The mean radius formed from over-laying those three groups on each other was 0.23”.


    best 10-shot group of hand-loaded 75 grain BTHP

    [​IMG]




    Here’s a pic of the composite groups side by side for comparison.

    [​IMG]




    Lastly, in a tribute to the Internet Commando, I fired two, 3-shot groups in a row from 100 yards using the control load. Both groups were sub-QUARTER-minute-of-angle.[​IMG]


    [​IMG]











    [​IMG]
     
  9. thegooch

    thegooch OT Supporter

    Joined:
    Jan 5, 2008
    Messages:
    15,580
    Likes Received:
    40

    75gr through a 1:9 twist?
     
  10. THT

    THT The easy way is always mined

    Joined:
    Mar 16, 2005
    Messages:
    12,748
    Likes Received:
    0
    Location:
    The booby hatch
    It's not optimal but my 1:9 stabilized them when I had it...shoot it and find out.
     
  11. johnson

    johnson New Member

    Joined:
    Nov 21, 2003
    Messages:
    38,412
    Likes Received:
    0
    Why'd you take the pictures down?
     
  12. fatmoocow

    fatmoocow bored OT Supporter

    Joined:
    Aug 27, 2002
    Messages:
    18,329
    Likes Received:
    307
    Location:
    the intarweb
    Note that the PPU may have undergone some changes over time. I believe the story was that is was slightly underpowered intially and they've bumped it up.
     
  13. yar1182

    yar1182 New Member

    Joined:
    Mar 26, 2008
    Messages:
    4,852
    Likes Received:
    0
    Location:
    Ventura California
    You'll have to evaluate through your own gun but word from the 3 gun crowd is that for a 1x9 the secret sauce is a 62gr hpbt. While some people claim they can get a 69 or 75 to stablize that may not be your case. I know my hot 75's don't do well out of my buddies 1x9 14.5". All sorts of keyholing and such. I think 1x9 along with a short barrel may contribute. I speculate if you had a longer barrel it might not be as obvious.
     
    Last edited: Nov 13, 2009
  14. mstad

    mstad New Member

    Joined:
    Apr 6, 2009
    Messages:
    2,833
    Likes Received:
    0
    Location:
    Oregon
    What ammo would be recommended for HD shooting out of a 16" 1/7 twist?


    ib12ga00
     
  15. THT

    THT The easy way is always mined

    Joined:
    Mar 16, 2005
    Messages:
    12,748
    Likes Received:
    0
    Location:
    The booby hatch
    75gr TAP w/ T2 bullet, not the .223 or FPD stuff.
     

Share This Page