Yesterday (Friday) the weather here was georgeous. About 80 degrees - and a stiff breeze. Today and tomorrow was predicted to be scorching (and it is ... )

I decided to take a few hours in the good weather - and hit the range.



What a day. Man - it was nice out there. Good thing too ... cause ... this time I remembered the gasoline for the generator if I needed it ... but forgot the fan ... haha. Good thing I didn't need it.

The previous video I posted last night was taken yesterday, and I did some long range testing. Started some shooting withw 3,300 psi. Worked good on the video work.



Walked the slugs up the backer, and then shot several into the plate.

They are tracking straight - all the way out. Out to 165 yards, I was using 3,750 psi in the pulse jet mechanism. There's a bit of tail drift.



You remember last time, I thought they were falling out between 185 and 200. I wound them up a bit more. Ran it at 4,000 psi. Straighten them out and got me 200 yards with the same accuracy - showing a hint of wobble - but they fly great.



Used the new paper plates - worked great. Great sight pic at 18X with the mil-dot scope. I've now set up the scope to dial in the elevation knob like a FT gun ... all the way out to 200 yards.

Had the clay Gopher out too. Did a video of him. I had one clay pigeon which I sat him up holding. Then, while fumbling with the "stuff" I needed for the video ... I bumped something, and the clay bird shattered in a million pcs. So; we got the orange spot target instead.



There's the entrance wound ... and the video will be coming.

The following two pics are the exit wound. Notice anything surprising?







Gary

Hi GB,

In the gopher entrance wound channel portion of this post, are those rifling marks i see in the wound channel?

Those colorful plates look really good down range. Looks to be a GREAT IDEA right there.

Good to always see a builder shooting what he builds.

Hi Ced ... or, shall I say "TOFAZ" ...

Yeah - on the EXIT wound ... I'd say they look like rifling marks to me. I'll have to count the tracks. It engraved the clay as it was emparting the energy to blow the wound channel out many times the size of the slug. The exit is probably 2" across.

Gary

Funny how those marks are straight. If they are the rifling marks which they appear to be, it kinda neat to think of how right at impact the bullets stops spinning.

Man, bullets really have a lot of STRESS stressed upon them during the entire firing to impact process.

For the guys that figure out the video. Don't blab - go make one for yourselves. Once everybody knows ... they'll all say ... Oh ... you mean you JUST ...

haha.

Gary

Nice pictures! I guess that seal blows out off the slug pretty violently but it does get engraved...

Yes - I think the slug is gone before the energy it imparted has moved the clay.

Sort of like that recent post I recycled from the Justice testing on a water jug. The hole in the target testified to the fact that the slug had been and gone ... but the following montage of slides showed the water's reaction building and building after the slug was ancient history.

Gary

Impressive groupings at Ultra airgun range! Makes me want to start pounding that 200 yard bell. I've got to have something around here that would do the job. It's nice to see you getting out to do some range testing on such a nice day.

Kent



Edited 1 time(s). Last edit at 07/04/2010 03:43AM by Cajun Justice.

Hello Kent,

Ya need to slide that 32 insert into your Chief Justice and give it a crack. That ought to have the spunk to get some slugs out there.



Gary

Hi Gary, interesting read and great shooting. I like the 8mm choice for the bore, German military caliber. Large enough to carry some weight, and still have a good coefficient for long range hard hitting work. I'll be following this one closely, the 8mm diameter has been used in wildcat rifle cartridges by a good many riflemen and for good reason. Appreciate the look into Barnes technology.
Joe

Hello Joe,

I've been interested, for years, in shooting some very long slugs. This seems to be working very well. It does make up a lot of energy, and seems to fly to distance very well.



Gary

Hi Garry,Nice groups for 200yrds.The rifling marks seem to have a left hand pitch but appear quite slow.As in most cases the rate of spin of a slug decreases at about the same rate as the velocity ,I would say that the the rifling in your 8mm is also quite slow.If you are running your LFC slugs they may need to be driven faster to achieve enough spin to stablize.Air rifles generaly tend to prefer slower rifling pitch's dependent on the length and weight of the slug you intend to shoot at what velocity over what distence.Good to see you pounding targets out to 200yrds.Danny

Gary, nice long distance work there indeed! It is surprising how accurate those slugs are even with some wobble. I'm starting to wonder whether I worry too much about a little bit of precession, as the best grouping slugs I have shot from my .308 show less than clean holes at 100 yards, but you can't sniff at 3 shots into less than 1/2 MOA. Bit of a mystery really.
Cheers
Neil

Hello Danny,

All Barnes barrels are left hand twist. A trademark choice from long ago. I've done quite a bit of testing with rifling pitches - from 1/7 to 1/48 over the last few decades.



Gary

That's very surprising to see rifling marks considering how much the clay has expanded, and it's apparent that you're still carrying a LOT of energy still at 200 yards for it to exit cleanly. That's way more than I'd expect of a .22LR round at that range, for sure.

Hello Rotor,

Because I had to trip the camera, and them hike back to the shooting bench while the camera was running, I deemed 50 yards to be quite enough for the clay video. haha.

As Kent mentioned though, you can see in the video, that the slug didn't seem to know it had hit anything. It really books along.

Gary

OK . . . surprised that no one's mentioned ith this thread, so I'll bite: please tell us about the choice of higher fill pressures (3750 and even 4000 psi). Can't remember another Barnes that took fills that high. And it seems to be working!

-- Jim

Hello Jim,

This is a "pulse jet" mechanism. Not a rebounding hammer. Therefore it uses a very short cycle burst of air. The shorter cycle can use much higher psi. Seems to work well.

Gary

Hmmmmmm. "pulse jet" huh?

Right ... the military are looking into it now Lon. It's gonna be BIG!



Gary

Is that the one with the unobtanium solenoid, or the valve seat made out of neutronium?

It's top secret, can't be discussed anywhere by anyone. Special forms must be signed and background checks completed for limited viewings at certain times and undisclosed locations. But you didn't hear that here.