.257 cal Monocoque First Tests

[rsterne]

Well, a year after this project came to a grinding halt, I finally got a day to take her out and let her stretch her legs a bit.... I built a new shooting bench, and the Monocoque was the first gun to try it out at 100 yards.... Here is a pic of the setup....



and here is a photo of the range, currently set up for 100 yards....



The field I am set up in has the ability for me to move the bench back to 300 yards, or pretty much anything in between.... The rancher I shoot Varmints for allows me to leave the bench and target stand in his field.... I have wind flags on stakes, currently at 25, 50, and 75 yards.... and recently purchased an anemometer that I keep on the bench with me....

The Monocoque was tethered to my Great White by a 3800 psi regulator, and I shot enough to use 1000 psi from the tank today.... I had 12 different bullets to try, or rather 4 different bullets, and three diameters of each, 0.256", 0.257", and 0.258".... The bullets were the HP and FN versions of my two heaviest Bob's Boattails from NOE.... The bullets tested were a 98 gr. HP, a 100 gr. FN, a 109 gr. HP, and an 113 gr. FN.... All bullets were cast in 2% tin....

The Millet scope is mounted on a Picatinny rail that I milled to angle the scope downwards, to hopefully center the POI at 100 yards with the scope centered, and it worked perfectly.... I was within 4" at 100 yards, and only need to tweak the turrets a bit to roughly center me with the 109 gr. bullets.... The 113 gr. were a bit low, and the 98 and 100 gr. were a few inches high, because there is an 80 fps difference between the lightest bullet, at 960 fps, and the heaviest, at 880 fps.... The first targets were 3 shots groups, intended just to prove that the POI was intended, and one of those was the best group of the day....



I saw a pretty clear trend, with the heavier bullets begin more accurate, and the smallest diameter the least accurate.... I'm not thrilled with the average 5-shot groups I shot today, but that 3-shot above, at 1.12", show that the gun has promise.... One thing is clear, the holes in the target are perfectly round, showing no sign of yaw, so the 7" twist is sufficient even for the longest bullets.... While I didn't shoot any groups today that would move me up out of Sharpshooter, I have a LOT to learn, not only about this gun, but about shooting cast bullets in particular....


Bob

[Ridge Runner]

This thing is AWESOME!

[Sfttailrdr46]

  Nicely done Mr Sterne

[Matt15]

Very Cool! Nice job, Bob! 

[marty2]

Nice setup and gun you got there. You should be upgrading soon.

[CraigH]

Great looking project!   

[Charlie51]

A very nice post, as always.  This is an amazing setup... (location, gear, and implementation).  You give one hope!

[screwwork]

Bob,

That is a big Prod! JK nice gun and great shooting too.