Velocity Change by bullet seating in 338 win

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by D.Camilleri, Sep 6, 2004.

  1. D.Camilleri

    D.Camilleri Well-Known Member

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    Jun 1, 2004
    I was just working up some loads for a friend today and along with the new loads I said lets try some of my 338 win loads in your gun and see how it does. First I asked him to check for fit in magazine. My combination was a tad too long for his magazine. I have a Rem. 700 and he has a ruger. The load is 78gr of Reloader 19 in front of a 200 gr. ballistic tip. OAL of 3.440 would yield 3100 fps in my gun. Due to the shorter magazine of the ruger I decided to shorten up the OAL to 3.365 to make them fit in his magazine. I also shortened up mine to see how the shorter OAL would work in my gun. In his gun they shot good, with about 2900fps. In my gun they only produced 2800fps. Does this seem reasonable? These loads always produced right at 3100 with the bullet extended further. I have noticed that the frontal shape is more tapered on the ballistic tip compared to some of the other bullets I have. It appears that by seating deeper I am getting some jump and thus loosing some pressure and velocity. Am I correct? I was starting to question my chrono but it seemed accurate with my 250 gr. loads. However, loads that I chronoed last week from my 22-250 that showed 3765fps(41gr H380,rem 9 1/2primer) showed 4000 today. I am baffled. Also one of the other loads I tried today for my friends gun was 73grains of imr 4350 in front of a 200 grain ballistic tip. This produced between 3100 and 3200fps, which was a tad bit higher than I wanted, but there were no pressure signs. I dropped to 72 gr. of 4350 and velocity came in at 2970. Isn't that a lot of change for such a small amount of powder? Factory remington ammo with 200 grain ballistic tips was producing about 2970 and they have the bullet seated to 3.310 OAL. I was having a little trouble with the chrono reading some shots so I colored the tips black with a permanent marker and that helped. Am I missing any thing here? [​IMG]