SHAWN CARLOCK Posted January 26, 2003 Share Posted January 26, 2003 I SHOOT THE 69 GRAIN SEIRRA MK EXCLUSIVELY OUT OF A 20" 1-9, WITH AN ACOG TAO1A. I GET SUB 1/2 MOA AND JUST AS IMPORTANT IS THE TRAJECTORY IT ALLOWS ME TO USE. MINE CLOCK AT 2800 FPS ON THE NOSE. IF YOU SIGHT THE ACOG AT 300 YARDS ON THE 300 YARD LINE IT WILL BE ON AT 400,500,AND 600. THE BEST PART IS THAT AT 100 IT WILL BE .75" HIGH AND AT 200 IT WILL BE 1.5"LOW USING THE 100 YARD CROSSHAIR. THIS ELIMINATES THE 200 YARD LINE. ANY PLATE INSIDE OF 225 HOLD DEAD ON. MUCH FASTER FOR ME. Link to comment Share on other sites More sharing options...
George Posted January 29, 2003 Share Posted January 29, 2003 Hi Kurt, Just got back to reading this and wanted to mention something about the G1/G5 data comparisons. The differences do indeed track in proportion for comparison purposes. The big improvement in the G5 drag model method (only if you are using boat tailed bullets that is) is that the path predictions are pretty darned close to the actual drop and drift that you get when you start testing. I have found that most ballistic software is OK for comparison purposes, but a little weak when it comes to getting corrections that really work. The RSI software gives you the ability to re-calculate the drag coefficients in a number of different ways. Most of which are a good bit closer to reality than the standard G1 based tables are. Here is a link to the download page for the free 30 day demo of Shooting Labs software. It does a lot of other stuff for ya, but it's main feature is it's unique approach to drag models. Talk to Jim Ristow at RSI if you are interested in more about his methods. http://www.shootingsoftware.com/ftp.htm Regards, (Edited by George at 4:18 am on Jan. 29, 2003) Link to comment Share on other sites More sharing options...
kurtm Posted January 29, 2003 Share Posted January 29, 2003 George: Thanks for the link! It,s always good to get more data. The new Sierra BEX program will also do the G5 for drag and I usually use it in that mode. The main difference I noted between the data we posted is in velocity, although after down loading the program and running them side by side the still diverge to some degree. Since this is America... we can buy the reality we want and all this goes to show NOTHING beats range time and a good data book for the particular tube you are using!!!!! Thanks again George!!!! KURT Link to comment Share on other sites More sharing options...
George Posted January 29, 2003 Share Posted January 29, 2003 Absolutely, the only thing that is right on the money is data from actual range testing. The day everything technically agrees to the nth decimal point, is the day it starts to get a little boring being a tech geek. It is good to hear that Sierra is using G5 data now. I will check out Sierras BEX software. I'm always looking for more data, can't have too much of that stuff, ya know :-) BTW, when setting the drag model in the RSI software, the best results are gotten from entering actual chrono results from multiple ranges (I haven't been able to chrono further than across 125 yards so my results with this method have not been as good as they ought to be). The next best method is to actually enter exacting measurements from the projectile in question. The third best method (but actually quick & dirty in comparison) is to convert G1 data to a G5 drag model. I have been using the G1 to G5 conversion method to get "what if" data real quick. The absolute best results I have gotten were by measuring the projectile shape, and doing slight corrections to the final BC by comparing it to my actual range results (mostly at 200 yards on my local range, with occasional forays out further to confirm. I have to travel a couple of hours to get any more distance), and then settling on a BC figure where the range results and the tables match up closely. Kinda ironic. eh? The tables I posted earlier were from the G1 to G5 conversion method. Regards, (Edited by George at 12:05 pm on Jan. 29, 2003) Link to comment Share on other sites More sharing options...
rkgsmith Posted January 29, 2003 Share Posted January 29, 2003 Last year at the 3 gun Nats. on stage 12 (?) the targets were obscured by brush and twigs. I noticed some members of my squad shooting 52 and 55 gr. bullets and some missed or key-holed on the targets because of the brush. It was nice to have a few boxes of Fed. 69 gr match to blast thru the brush. I'm a big fan of 55 gr under 200, and 69 over 200, or when the need arises to trim some hedges. Link to comment Share on other sites More sharing options...
kellyn Posted January 30, 2003 Share Posted January 30, 2003 I must disagree with youur conclusions rkgsmith. I shot that stage with a .260 remington FAL shooting 140 grain bullets and had 2 misses shooting through that brush. The brush was only about one yard in front of the target. Steve Hendricks told me he could see my bullets hitting the brush right in front of the target and I called them as good shots albiet through the brush. Heck I was only about 10 yards away. As far as I know those bullets are still tumbling through space. Two other bullets keyholed into the target. If a 6.5mm 140 won't reliably make it, no way ANY other bullet below a .50 will. I would have been nearly even with Bennie if I had not had those 2 mikes. Lesson: NEVER SHOOT THROUGH BRUSH. Link to comment Share on other sites More sharing options...
kurtm Posted January 30, 2003 Share Posted January 30, 2003 Kelly, Kelly, Kelly: What makes you think a .50 doesn't deflect also? Having spent some time with .50 ball for the old M2 and a quest for just what it would do, I can definately state it will deflect also. Albiet not as much as say a .308 but A LOT MORE than you would think!!! With a target 10' behind a bunch of twiggs( non bigger than a pencil, and you could see the target through the screen), we had two hit the target 7"-9" from point of aim, one showed signs of starting to key hole 12" from point of aim, and 2 missed the target entirely. Target was at 500 yards!!! I think that if it isn't fired with a lanyard, it probably doesn't do well in brush. KURT Link to comment Share on other sites More sharing options...
skeeter Posted January 30, 2003 Share Posted January 30, 2003 at our club we have a little jungle course that we use from time to time and we set up shoots that most go thru brush. and nothing makes it through all the time. Link to comment Share on other sites More sharing options...
kellyn Posted January 30, 2003 Share Posted January 30, 2003 Kurt, Kurt, Kurt, I am aware that .50s deflect, as will any projectile. I was using an extreme example. But I suspect a .50 would have made it to those paper targets at the 3 gun nationals. Link to comment Share on other sites More sharing options...
kurtm Posted January 31, 2003 Share Posted January 31, 2003 KELLY: I am sure you are right, but then Bennie would still have beat you as even the best .50 mag capacity is 10 rounds ( belt fed I'm sure is in open) and splits are realy slow. ALL of this and the last one was ment in hummor except the deflection part. NO ONE was more suprized than I! KURT Link to comment Share on other sites More sharing options...
rkgsmith Posted January 31, 2003 Share Posted January 31, 2003 Kelly, I was not implying the .69 gr .223 was some type of super duper brush defeating bullet. I was simply bringing up a point the .69 had a higher success rate on those targets than the .52 and .55 gr. The .69 will penetrate more and deflect less than the .55 (generally) on similar material. But maybe I'm wrong I only finished 8th on that stage "clean." Link to comment Share on other sites More sharing options...
SGDM Posted January 31, 2003 Share Posted January 31, 2003 Hey Kurt, My .50 cal mag holds 600 rds x 2 and I have never seen anything "deflect" the .50, not even Russian steel!! hehe Link to comment Share on other sites More sharing options...
kurtm Posted January 31, 2003 Share Posted January 31, 2003 SGDM: See that would make it an open....er. Especially on bpms and btrs, but be careful on any of the T series. KURT Link to comment Share on other sites More sharing options...
kellyn Posted February 1, 2003 Share Posted February 1, 2003 KURT, Bennie always beats me, and when he isn't, you are. SGDM, You make me feel feel like my tax dollars go to a good cause. Thank you. rkgsmith, I agree that 69s have a better chance of making it but I'm super leery of brush after that experience. Out of ALL the shooters there, my gun had the best chance of making it and failed. Link to comment Share on other sites More sharing options...
kurtm Posted February 2, 2003 Share Posted February 2, 2003 SGDM: OOPS......BMPs, oh well its all just tread head stuff anyway!!( "darn wisky" Kelly: When you and Bennie aren't beating me I am beating myself.... except it costs me less as I shoot "light" bullets!!!! KURT Link to comment Share on other sites More sharing options...
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