Possibly OT but: 7.62x39 110gr Sierra HP and Hodgdon H4895

Discussion in 'Reloading' started by westcliffe01, Jul 15, 2011.

  1. westcliffe01

    westcliffe01 Well-Known Member

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    I have an AR47 (DPMS 7.62x39, 16" bbl) which I am getting tuned in for hog and coyote hunting. I have lots of FMJ 1970's and 80's Yugoslavian ammo (shoots real nice with beautiful brass that I am prepping to reload with the usual berdan wrinkle..). I also have lots of S&B 123gr soft point ammo.

    I am experimenting now with a 110gr 308 hollow point from Sierra. I am looking for a load that is a little flatter shooting with a bit more muzzle velocity, while being inexpensive to reload. I have also heard that reliable expansion of the bullet can be a problem given the anemic muzzle velocity of this round. Particularly for the coyotes, which might be longer shots I would like something with better expansion potential.

    My Hornady reloading manual does not list Hodgdon H4895 loads for 110gr bullets. However, it appears that for a 125gr spire point, a 29gr load is recommended. I know that 28gr of H4895 fills the case to the base of the neck. 29gr would probably be half way up the neck.

    Does anyone have software to do a load calculation for this combo ? I am using Sellier & Bellot once fired brass (boxer primed). When does a compressed load become a problem ? The H4895 is not a very dense powder due to the long grains.
     
  2. westcliffe01

    westcliffe01 Well-Known Member

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    Ok, first attempt was a bust. Note to self, full length size any casings for a semi auto rifle... I neck sized only and the round wouldn't chamber all the way. So I have to pull the bullets, dump the powder and do a full length resize.
     

  3. Natty Bumpo

    Natty Bumpo Well-Known Member

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    Does the DMPS AR47 rifle have a .308" caliber barrel or .311"? AK47's have .311 caliber barrels. Sierra's 110 grain, thirty caliber bullet is .308" diameter. They make .311" bullets in 125, 150, 174, and 180 grains. I would assume your Yugoslavian and S&B ammo is .311 caliber.
     
  4. westcliffe01

    westcliffe01 Well-Known Member

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    You know, I do not know whether DPMS has a 0.310 bore or a 0.308" bore. DPMS has "purged" their website of all information relating to the 7.62x39 after the embarrassing C Products fiasco. They also refuse to answer questions on the support forum. I don't have time to call during the day. There would be no risk in trying the 308 cal bullets, since it would not be an interference condition, so I am not concerned. If 308 is really too loose for accuracy one will find that out pretty quick when the groups suck. I only managed to fire 2 bullets today, the balance wouldn't chamber, but the 2 I fired struck right at the POI, so accuracy seems fine if I can get on top of making the brass work with the rifle.

    So far the trigger has dominated the accuracy issue. I noticed today that the trigger was a LOT better than ever before, but I also noticed it would not reset if released after putting some pressure on it and this I do not like. The sear engagement is really substantial, so I am going to try a stronger trigger return spring first (or more preload, since the movement is small). If this doesn't work, I have to re-cut the sear with a more positive engagement angle.

    I don't know if others agree, but I personally need a much larger diameter pistol grip to put my trigger finger the right distance to the trigger itself. Right now my finger is cramped when trying to engage the trigger with the fingertip.

     
  5. RT2506

    RT2506 Well-Known Member

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    You want expansion in a 7.62X39? Look no further than Hornady .310 diameter 123 gr V-Max and a case full of AA 2015 for around 2400 fps.
     
  6. westcliffe01

    westcliffe01 Well-Known Member

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    Where do you find these bullets, since they are not listed on the Hornady website, nor Midway USA, nor Brownells ? Hornady lists only 2x 310 bullets, a soft point and an SST. In the 308 Vmax they have the 110gr only ???

     
  7. dust

    dust Well-Known Member

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    Interested in what you find out about the barrel and the loads. Have you considered loading heavy for caliber and shooting subsonic?
     
  8. RT2506

    RT2506 Well-Known Member

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    I got the 123 V-Max from Midway a while back.
     
  9. westcliffe01

    westcliffe01 Well-Known Member

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    I have thought about subsonic, but on further reading it seems subsonic is a risky business in a semi auto, where you really need a jacketed bullet to feed. In a bolt action where cast lead bullets will chamber with no problem, it is much more viable. But the drag of the long jacket on a heavy jacketed bullet increases the risk of getting a bullet stuck in the barrel significantly and then when you shoot the next round the barrel blows up and you stand a very good chance of being severely injured....

    With the way the barrel and bolt in an AR is configured, it is enough of an achievement to get soft point bullets to play nice, let alone an unjacketed bullet.

    I'm also not sure I would like to be shooting coyotes with a subsonic round, since they are pretty skittish and just getting them in range can be enough of a problem.

    The situation with the Vmax bullet is weird. I have a Hornady LockNLoad press and it came with a 7th edition Hornady reloading manual. On the page for the 7.62x39 round, they show a 123gr Vmax (part #3142) and the caliber is shown as being 0.310". The 110gr bullets are all 0.308", as are the 130gr and 150-155gr. So 123gr is apparently the only bullet made in 0.310".

    Yet, when I go to Hornady website, the same part number 3142 now comes up as an SST. Perhaps the function is the same, but the name changed since the reloading manual was printed.

    best part is that I have not found anyone yet who carries stock of that particular 310 diameter 123gr SST bullet... Even when looking under the right name.