308 Winchester ballistics, help!

Discussion in 'Shooting, Hunting and Fishing' started by TRAZTAZ, Aug 3, 2009.

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  1. Need a little help, just taken a shot and completely missed and very unsure why.The ammunition was Gecco Target 170 Grain.I shoot a remmington 700 which has been customised.I have used this ammunition for years with no problems at all.I shot at a Roe buck at exactly 194 meters, and made an allowance of about 6 inches for bullet drop.The rifle is zeroed a cm high at 100m.The buck showed no reaction to shot, and as I tried to reload the rifle the bolt was extreemly hard to open, I mean very hard to open.
    We searched the area after the shot with a blood tracking dog, found nothing , and then spotted the buck in a wheat field, deffinatly nothing wrong with him.Will sit again tomorrow.
    Bar the fact that I could have pulled the shot in a big way, has anyone any suggestions? The fact that I had a hard extract has got me thinking, bad cartrige maybe?There appears to be nothing wrong with the cartrige by the way.
  2. Probably shot clean over the top. Drop at 200 with your zero should be around 2-3 inches. Bad hold+pulling shot=clean miss.
    • Like Like x 1
  3. Have a feeling it was carp shooting, but the hard extract worries me, hope it was no more than me doing the buck fever as this one is special special, post pics tomorrow if succesfull.
  4. Is it a white one? :)
  5. Alsacien

    Alsacien LE Moderator

    Gecco is not the highest quality ammo, suggest you take the same box to the range to confirm nothing is wrong with the zero or ammo batch before shooting again at live game.
    Sounds like over pressure. Unlikely to be too much charge, so check the crimp on the other rounds. Could that round have been damaged?
    Would expect -12 to -15cm for a rifle zeroed at 100m shooting at 200m with .308
  6. I've just been playing with the ballistic calculator, and bizarrely the 150 grain Match King and the 135 grain Match King have almost identical ballistics in the range I am looking at (2167 feet per sec, yes there is method behind that number!). Intriguing...
  7. Sounds like:

    Something obstructing the breech chamber surface, hence the difficult extraction, or a mis-formed case, giving the same problem. If the chamber has got rusty, or metal particulates in it, then the case will blow into them and be difficult to get out.

    Apart from that, the missing the shot bit could either be a 'bad round' or a 'bad shot' :D
  8. I would say you missed over the top for sure, especially with a Roe, and also considering you have shot that rig for years.
    For the record Geco 170gr is superb ammunition- bullet quality is top notch and the brass is pucker. It's RWS lite.
  9. Alsacien

    Alsacien LE Moderator

    Geco is RWS without the quality control, hence the difference in price. Good stuff for the price for sure.
  10. Do you still have the case?

    What was the primer like? ...any extrusion or signs of high pressure?
  11. Just possible that the bullet broke up in flight. Rare event so most shooters tend to discount this because there are of course so many other more likely variables to choose from but it can and does happen.

    Do not need a great deal to be wrong with a projectile spinning at very high rpm.
  12. Not so sure that would happen with a 170gr bullet. It's not spinning too much and it is going relatively slow.
  13. ugly

    ugly LE Moderator

    Watching and wondering, missing deer, especially dead certs does happen. Stiff extractions is usually a case/pressure/sizing issue.
  14. True, but even at 2000fps out of a 1 in 12 barrel it will be rotating at 120,000rpm. If out of balance or with a weak point in the jacket they can let go but as said, very rarely.