Mark bumped up our loads last week and we were able to get the 175’s flying at 2,570 which is as little better. He loaded with 43.8 Varget and accuracy was very good.
I am getting a new scope and curious how I build a chart the shows based on bullet weight, speed, BC…you need "1? clicks to hit 600 yards or whatever it may be.
I have heard there are online charts for this, but I never played with them. Any help =gracias!
I have NF software on my PDA it works very well! Here is a link you have to sign up but this progam will save your loads and you can print the drop data. THere are programs for your android phone or your ipod
Cheapest way to get what you are after, is the way I do it. (for something you can take in the field anyway)
Buy a Kestrel 4000 or better.
Buy an iTouch.
Buy an otterbox to kee the itouch dry and protected.
Download “Ballistic FTE” from the app store.
I keep my itouch in my databook. Ballistic will give you a firing solution based on your load and current conditions. It’s been accurate to within a tenth of a mil for me on everything I’ve tested it with, including 308 out to 1540yds.
Another app to try is “bulletflight” by knights armament. It is not as powerful as Ballistic, but is easier to use for beginners and still very accurate to 1000yds. Can’t say I’ve really used it past that, as I kind of “out grew” it before I started pushing past 1k yds.
cool. 
Some good info here. I have been using “Bulletflight” on my iphone and it works pretty well for my, limited knowledge, needs. My only issue is that I don’t have a chronograph to get accurate MV numbers from my rifles. I only shoot commercial ammo (BH, Hornady & FGMM) so I try my best to find relatively accurate numbers for my barrels via the internets. I do like Orkan’s idea of the Kestrel and ipad, hello Christmas!
I only use the software for my LMT .308 with 16" CL barrel and my 16" BCM SS RECCE, for now. Will be getting a bolt gun in the coming months.
You can also do this on the internet and print it out.
As some have mentioned you’ll also need weather info. The most accurate way is with a Kestrel NOT the cheapest way though.
If you have an Iphone I use a program called Ballistic FTE. It works great. It even uses the same algorithm as JMB online.
Taking charts with you does not account for environmental variables at your shooting location. It’s nice to have them around for a fallback, but in that case I have my actual dope cards to wing it off of.
To get really accurate, a kestrel with an interlink to a trimble nomad is about the best you can get. Very expensive though. Around $3500 by the time its all setup with what you need. It’s bigger and heavier too.
My iTouch is small, and cheap. Kestrel, iTouch, and the databook all have their place in my pack.
Im having the same issues as these… Has anyone here chrono’d 175 gr FGMM out of a 20" barrel (preferably factory remington)?
Federal’s site lists it at ~2600 fps, but i think that is from a 26" barrel.
From Sierra’s site
http://www.sierrabullets.com/index.cfm?section=bullets&page=bc&stock_num=2275&bullettype=0
mil----after clicking link, back space, change to moa if that’s what you have. you can also change the data, I put in certain temps and likely DA based on your AO
Doubt it’s going 2600, I know Blackhills advertised at 2600 with their 175’s and with an sps, lucky to break 2500, I was getting 2475-2500, another shooter got 2525 from a 22" sneider barrel.
I agree with Mark, dont go by what the manufacturer says. I ran into the same issue with BH and Corbon.
Out of my 25" AI with can I got about 2585 for both BH and corbon.
You really need to chrono it out of your gun to get accurate MV.
With an accurate chrono. It’s a very common thing for cheap chrono’s to be +/- 100fps or more.
Well not an expensive chrono but my Prochrono reads within 10fps of my buddy’s Ohler.
59 degrees, moly’d 175 smk’s averaged 2641fps with RL15 in my XCR Tactical, a stainless version of the LTR, 20" barrel.
If you have an Android device: Shooter
Screenshots at link.
That is very fast out of a 20" barrel.
True, but you can confirm MV by going out shooting and comparing the data to your actual dope. It’s truing the gun.
Actually, that is tuning the ballistic calculator. Knowing true muzzle velocity and inputting the correct variables into ballistic, and having it output the correct dope… that is the goal. Then if it is accurate at one condition, it will likely be accurate across the range of conditions.
Shooting the rifle at various ranges, and fudging the numbers in the ballistic calc to match what you see, only ensures that the trajectory matches at THAT specific condition. Now, it will be close, sure… but it isn’t unrealistic to see a 0.3-0.5mil variance the farther you get away from your “tuned condition.” This practice reinforces bad data, and shouldn’t be encouraged.
Obviously I agree that real world shooting needs to be compared to what your calc is showing you. Otherwise you won’t be able to trust its numbers. However, there is much more to it than just changing the numbers in the ballistic calc to suite a trajectory from a single range trip. (not that I was inferring you said that) For instance, bad numbers in your ballistic calc can also be an indication of a scope turret that does not track correctly or a reticle that does not subtend correctly. Those are just two of the external variables that can affect your perceived dope inaccuracies.
If you shoot the 175 SMK you should check out the FDAC:
http://www.actsvirginia.com/sliderule.php
While I agree that a kestrel and ballistic computer are best this is great solution that costs way less. I have one and have been quite impressed with it. Its easy to use and has given me fairly accurate drops.
A friend of mine just has his new 270 WSM out in preparation for his upcoming deer hunt. He used his chronograph and obtained his velocity. He then shot at 500 yards, and when the corrected drop was entered into the G7 program, the corrected velocity ended up being 218 fps. lower. I’m assuming the corrected drop chart, at all the different yardages, will be spot on, but that seems like quite a bit of a drop. I don’t get how the velocity could be that far off. I haven’t heard of anyone speaking about the accuracy of chronographs. Anyone have any info. on this?
Oehler 35p
PVM-21
Those two chrono’s pretty much rule the roost, with the 35p being the elder of the two.