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View Full Version : Jump to lands



tippet
04-16-2014, 09:29 PM
I have a Model 12 .223 with 1:9 twist. I want to try a Berger 52 or 55 Target bullet with H335. Rather than trying a wide range of jumps to lands, and wasting a lot of ammo, can someone give me decent range of base to ogive or jump to start with? Thanks!

Luke45
04-16-2014, 11:22 PM
Not sure if this is the proper way to do it, buts its always worked for me. Ive picked a powder i want to try, then i start 5 thou off lands mess with powder from min to max in incriments untill you find the best accuracy with a given powder charge while watching for pressure signs. Once i knwo what wieght of powder shows the most promise i then make a batch of shells at that weight powder at seating depth incriments just off the lands to 25 thou off or so, 5 shells each at each OAL . once you find the most accurate seating depth then i mess with the powder a bit higher or lower to see if i can further gain accuracy. this process usally takes 50 rounds or so. IT usually produces 1/2 moa after only 50 rounds fired or so for me with pretty much all my bolt guns, and if it didnt i would switch powder or bullet and try again. Again this probably isnt the proper way but its a quick easy way and only take 2 or 3 trips to the range. Is see posts about people doing ladder tests, ect which is probably more scientific way to do it though

tippet
04-17-2014, 06:03 AM
Thanks! It looks like you select and ladder the powder first, next select the bullet, and then determine jump. An interesting approach that deserves some thought.

Luke45
04-17-2014, 08:22 AM
Well I select the bullet first as well as the powder! Do I do this way different than most? I am a self taught reloader and started when I was 11 so I probably have some bad habits

RyanG
04-17-2014, 08:41 AM
Luke,

I hope that its not too wrong..... I do it exactly the same way

Luke45
04-17-2014, 10:04 AM
ive been doing it forever and it works for me so why change it!

ghostwriter247
04-17-2014, 10:15 AM
Me too!

stomp442
04-17-2014, 12:39 PM
I do things the same way except that over the years I have found the sweet spot in most of my rifles to be at 20-25 thou off the lands. I start there and adjust powder charges. I can generally find a great load pretty quickly.