I went over to the range this afternoon. Final testing for the 25 Rendezvous - and gathering BC information on the Barnes 87.2 grain nine ring commercial slug.

In addition, here are a few pix to augment a couple of my comments to posts recently.



Heavy weight bullet trap suitable for heavy big bore.



Snail Shell scroll and baffles trap and decelerate the slugs. Dump the lead smears thru the slot at the bottom.



The internals turn the heavy bullets into lead sheet



I shot the 45/08 with the Barnes bishop for a couple of groups to finish the sight-in.



Love this rifle format.



I set up to gather all the information to determine the BC for the Barnes 9 ring 87.2 grain slug for 25 caliber.



Setting the threshold lower for the "smile shutter' on my new camera. Even a mild pleasant smile is recognized by the tracking and the shutter trips! Face recognition internal software ... in a $126 camera. Love this value. I'm a big fan of the Sony Cyber Shot Series. I've had them over 10 years.



The carving on the steel of the 25 Mag.



The 25 Magnum during gathering the chrono numbers for the BC determination.



And, one last pic of the carving, with the final coat of oil baked on,

Hope you enjoyed the pics.

Gary

Nice post Gary. I downloaded Chairgun and ran the numbers.... .0470!

Edit: The above was with all shots included. If I toss out the high and low value from both data sets, the BC comes in at .049. We so need to get numbers for the 7 ring now...



Edited 1 time(s). Last edit at 01/21/2009 04:11PM by Jerry.

Hey Jerry,

Good work. That sounds like it should be pretty "slippery" in the air!

Gary

Jerry: did you factor in ambient temp and altitude? I found that when I did this, my numbers were different by .02 or so.

I still have some data for the .45 Bishops I need to crunch. I'm thinking that will become the "default" slug for the Delta due to its accuracy.

-- Jim

Hi Jim,

Yes .. I gave Jerry all the nos. 29 degrees start - throughout - and finish. 3 yard first phase, and 42 yard second phase. 500 ft. elevation.

You would be wise to count on the Bishop - yes. It's always been a great round. They cast nicely too. I've settled upon it for the default for the 45/08 too.

Gary

Gary, Gary Gary (said in a condescending manner), you have missed a very important step in your testing procedures, which is this.....no one knows how your guns perform in the Southern Hemisphere...so, you need a special agent (me, for example) to carry out exhaustive tests, taking into account the coriolis factor (something to do with how the water goes down the plug hole in a different direction way down here). Anyhoo, I imagine the testing would only take 10 - 20 years, after whch I would express-freight the subject back to you on the cruise ship I posted a pic of a few weeks back. Whaddaya say, huh?

Neil, Neil, Neil ....

That's why I rifle all my barrels with a left hand twist ...

However; I will consider your gracious offer. Now - how much would you want me to pay you for your expert testing program. I've seen the pics of your place there. I'm not sure I can afford such splendor.



Gary

OK. I'll work out some pricing

You have the 25 magnum shooting very nicely by the look of it...someone is going to be a very happy camper!
Cheers
Neil