GTA
All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Big Bore AirGun Gate => Topic started by: rifle50 on October 14, 2015, 09:02:43 PM
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I have tested some aluminum tips for a NOE 80 mold around AUGUST this year....Erik Ohlen at Hollow Point Mold Services had told me mid summer of ideas he had....I agreed to H.P. my mold and do some testing. He made up a few tips and furnished a PUNCH to put tips on with. Punch replaces the punch of a LEE TYPE SIZER...
I guess Erik furnished 100 tips, didn't count....I shot them at 100 yds. The Regular NOE and the TIPPED version was as good, and grouping was a little MORE ACCURATE., that particular firing sequence...I wasn't interested in 100 yds anyway, but if they had been terrible in accuracy i would have gone "NOE" further ::)
A week later i tested for B.C., 50 yds over 2 CHRONOGRAPHS at the same time.....
I usually shoot 6 shots but if one is abnormally high/low in the string for fps, i may shoot 8.....I throw out the ODD SPEED and average and insert in the JBM B.C. Calculator........
B.C. for the FP NOE 80 was .303 and with the tipped version right behind these and they were .393 B.C. THAT IS 29.7% INCREASE!!! And it makes a big difference at distance for LESS DROP.
I ONLY had 25 tips left.....Another of my trips to the steel plate and 800 yds....Shoot dirt spot first to see elevation on scope with the regular NOE 83 gr.. .I get on the dirt at 800 yds, with proper elevation... Shoot several more to confirm and in MIDDLE of cleared patch of dirt for elevation. I knew the TIPPED ONES with better B.C. Should hit higher and I aimed at the BOTTOM of my cleared dirt patch and shot kicked dust at the top, almost in weeds high....WOW, i go that is 8-10 feet HIGHER...I use another mil-dot and shoot to middle of dirt patch....I then drive down and put steel plate up and come back, shoot couple more into dirt RIGHT of steel and elevation seemed about same?
I made a small mistake....BACK at my bench/shooting position, the TOP of the steel plate view behind was in the weeds..I started firing and DIDN'T SEE DUST so figured hitting steel.....Shot the TIPPED rounds i had left and drove down....All but 3 went high over the top and i didn't see any dust and didn't know....The 3 that hit were at the top 2 inches of the plate. I since have plate LOWER in the bank and can see dirt OVER the plate...... Anyway the bullets are much more efficient in flight...Plug into the Hornady Ballistic Program, the 1015 fps that bullet flight hit little over 9 feet higher at 800 yds over the standard nose...At 800 yds that is 10 MOA LESS elevation needed.
Erik is now making smaller pins and tips, and punch for the Lyman 72 gr mold... I also bought 100 more tips to do again at distance some day with the NOE 80?
Pics of the bullets with tips. the pic with several bullets I shoot, are the Noe 63, Lyman 72, Noe 80, Noe 81 tipped, LBT 92, Noe 104. That NOE with the tip is LONGER than the 92 grain.
Comments Welcome. Pics enlarge when clicked.............Carl
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Good report Carl!
The one thing I was looking for in the report wasn't there. The one thing that needs to be known about a hollow point. ( it's very reason for existance). Eric and I surmised that not only would the tips increase the BB, (that was a given). But by how much ----Thank you for that info. But we figured that the tip would cause the bullet to open faster, and NOT get clogged with thick hair in winter pesting. Did you not check for the one thing a HP is for, especially the difference the tip would make?
Knife
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Good report Carl!
The one thing I was looking for in the report wasn't there. The one thing that needs to be known about a hollow point. ( it's very reason for existance). Eric and I surmised that not only would the tips increase the BB, (that was a given). But by how much ----Thank you for that info. But we figured that the tip would cause the bullet to open faster, and NOT get clogged with thick hair in winter pesting. Did you not check for the one thing a HP is for, especially the difference the tip would make?
Knife
Reason the info was lacking is I DIDN"T RECOVER THE 3 BULLETS that hit plate...I was so perturbed i didn't realize bullets were high and missing it, and had NO MORE LEFT....Also when first using the plate i tilted it rearward.......This tilt with sun washed out the video with glare, and bullets deflected ANYWERE and didn't get to check that fact....I now tilt plate forward some and hits deflect straight to base and get a handful....What i DID NOTICE THOUGH, instead of that half inch black spot of the hit, the 3 that hit AL TIP was not very large impact imprint, maybe half the mark in size....I thought at that instant that the tip prevented opening??? But don't have evidence to actually see.......With a FP smashing as they do, I can't see why at impact the force actually HELPING OPEN, like driving in a wedge?? But steel different than flesh.....
As mentioned I have more points coming and Erik called Monday and sending them.....Probably won't go to long range but may just shoot the plate at 200 yds for the information and can do at the local range that part...
That is reason for why I didn't have anymore info..............Thanks MIKE.........I will report WHEN i have something useful....................Carl
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Looks like an idea I posted back in "mid summer" http://www.gatewaytoairguns.org/GTA/index.php?topic=93805.0... (http://www.gatewaytoairguns.org/GTA/index.php?topic=93805.0...) Glad to see some testing!!!
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Carl, just ragg'n ya. I just got off the phone with Eric, and he told me that you weren't really interested in expansion, but did need bc. Looks like worked! Backing plate markings tell you next to nothing about expansion. More that likely, the smaller mark, was the result of the bullet's blowing up very slightly before actually making contact with the plate, rather than not expanding. (Milliseconds here) The nose will act almost like a detonator if you will.
Eric and I had been talking about different way to make a HP open fast at lower velocities. He had wanting to try a few projects for years, and this warmed him up on it again. LOL!!!
I had been playing with using inside cutters to score the cavity walls of the HP's to make them open in a petal pattern, and was telling Eric my experiences many moons ago with the then new Nosler Balistic Tips. They literally blew the first Doe that I shot with one from a .257 Weatherby Mag. In half. The deer was ruined. Nothing but blood shot meat.
Turns out, that a Ballistic tip speeds up expansion rather than slowing it down. Which is exactly what I am looking for in an AG Bullet.
So we can have higher BC. Which will give us better wind drift characteristics, greatly reduced drop, along with higher down range fpe, and if done well, with better accuracy to boot!
I'm looking at ways to make it cut the interior of the cavity as well. Eric and I talked about that as well tonight.
It's an exciting time to be in AG's! Guy's!!! Gotta Love It!
R-!, yes, I remember your post. "IF" you can get the proper fit, it's a good combo! I really liked the results I got on varmints. 8)
Knife