No mention of what your jump space is. COAL varies per bullet shape. Jump space is the distance from the lands and grooves to the ogive of your bullet.
"Jump space" is a term no experienced handloader would ever use. It's simply the bullet seating depth -- the distance between a the bullet ogive and the start of the lands -- and is a function of the barrel's throat length. X-Ring Newsletter - Sierra Bullets - The Bulletsmiths
Once he has established his seating depth -- whether it's 0.010" or 0.015" or 0.005" short of the lands -- it will (in theory) remain constant for any bullet used in the given rifle, provided it can be accommodated in the magazine, too. He is using the same bullet in both sets of his loads and firing through the same rifle, making your suggestion moot.
Keep on going Tcox, chasing the ultimate accuracy of ones rifle is half the fun to long range shooting. If you can reproduce what you've already done on your next range trip check its validity from 100-xxxx yards. Consistency is the key to hand loading.
You're shooting a 6.5 creed correct?
You're shooting a 6.5 creed correct?
I returned today, but only to continue further development at 300. I stayed with my best charge weight and played with depth. I moved in .005 increments starting at 2.940" and moving deeper to 2.920 (contacting lands at 2.945). As expected the hybrids liked a .010 jump. I loaded 7 to those specs and shot a .481" group center to center. My strings were mostly horizontal so I suspect most of the play in the group was me. I'm really surprised at how well my rifle is shooting and better yet, I had a witness for this trip. Hopefully I'll be able to get to the farm and go further than 300 sooner than later.
I'm pretty surprised by the variance in overall length of these. The distance to the ogive is pretty consistent, but the projectile over all length varies by +\- .005. According to what I've read, it doesn't have a substantial effect on accuracy.
Jcann: yessir, I'm shooting a 6.5 creedmoor built by Norbert Costa.
I'm pretty surprised by the variance in overall length of these. The distance to the ogive is pretty consistent, but the projectile over all length varies by +\- .005. According to what I've read, it doesn't have a substantial effect on accuracy.
Jcann: yessir, I'm shooting a 6.5 creedmoor built by Norbert Costa.
Good shooting! I've been following your thread. Your right, variances do make a difference.
The same round in a different rifle makes a huge difference even though they may be "mil spec". Small differences in length can and will have an effect on pressures and accuracy.
The best guru for pin point accuracy was Carlos Hathcock. One of the best snipers in Vietnam.
When he taught precision rifle, his students came to the range with mags full of ammo. He had them set up, put in their dope for the range they were shooting at and take the shot.
When they took that shot, He told them to go home, clean their gun and come back tomorrow. Take one shot, and repeat the drill to go home and clean.
His training was for a cold bore shot to be the most accurate. Similar to what a hunter needs. Shooting 3 shot groups for hours proves nothing for a hunter or a sniper. It only proves you can get a group after your barrel warms up.
You need that cold bore shot to be the most accurate for that discipline. If your into long range steel or whatever, a lot of folks shoot one into the dirt to foul the bore, and warm the barrel and then shoot.
Sorry to ramble so much, but It all depends on what your intended purpose is to set the rifle up for.
The same round in a different rifle makes a huge difference even though they may be "mil spec". Small differences in length can and will have an effect on pressures and accuracy.
The best guru for pin point accuracy was Carlos Hathcock. One of the best snipers in Vietnam.
When he taught precision rifle, his students came to the range with mags full of ammo. He had them set up, put in their dope for the range they were shooting at and take the shot.
When they took that shot, He told them to go home, clean their gun and come back tomorrow. Take one shot, and repeat the drill to go home and clean.
His training was for a cold bore shot to be the most accurate. Similar to what a hunter needs. Shooting 3 shot groups for hours proves nothing for a hunter or a sniper. It only proves you can get a group after your barrel warms up.
You need that cold bore shot to be the most accurate for that discipline. If your into long range steel or whatever, a lot of folks shoot one into the dirt to foul the bore, and warm the barrel and then shoot.
Sorry to ramble so much, but It all depends on what your intended purpose is to set the rifle up for.
Hathcock was ingenious. Definatly a legendary idol for many. Chuck Mawhinney is also a Vietnam legend that doesn't get much credit. My hat goes off to both of those boys. Think I'll toast to them and the hundreds of Hero's that were the silent professionals tonight.
Does anyone have any experience with variation in projectile weights? I weighed a box of 100 of 140gr hybrid targets and the box varied from 139.83 to 140.11. That's not much but with the purpose of this rifle being for ELR, would this be of any substantial concern? I also need to get a bullet comparer or headspace gauge to see my actual consistency, I worry about the large projectile variance of .005
Does anyone have any experience with variation in projectile weights? I weighed a box of 100 of 140gr hybrid targets and the box varied from 139.83 to 140.11. That's not much but with the purpose of this rifle being for ELR, would this be of any substantial concern? I also need to get a bullet comparer or headspace gauge to see my actual consistency, I worry about the large projectile variance of .005
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I would concern myself more with getting a chronograph and a ballistic app and shooting the crap out of your rifle. You haven't even stepped into the range where wind reading defeats the best hand load. A 6.5 creed generally isn't considered an ELR cartridge
Challenge accepted lol! I know a few guys that have pushed theirs to 1450 on silhouettes. Granted they are MUCH more skilled than I am. I agree, it's certainly not ideal for ELR but it's what I have for the next two years. I would agree that I need to go shoot the crap out of it. As well as a chrono, there is quite a bit of equipment that I would like to help me get there. I don't make much so acquiring more equipment is slow, so for the time being I want to push really hard to get everything as uniform as I can. I'm hoping I can take every advantage available to me now, even if it's not time-efficient.
Depending on atmospheric conditions and using 1500 yards shooting 140gr Berger Hybrid at 2,850fps you're still supersonic @ 1,122fps. With a 10 mph 3 o'clock wind you have a drift of 166", with a 9 mph wind you have 149.4" of drift. Are you good enough to call a 1mph wind difference and will you be able to see your bullet splash to adjust?
Speaking from personal experience, wind is the great humiliator and can turn a day of fun into a day of frustration.
Speaking from personal experience, wind is the great humiliator and can turn a day of fun into a day of frustration.
I have some experience as well, not likely as much as you do. I would agree that there is nothing more humbling than wind. It'll be important to find a few mentors. To answer your question, no. I am far from good enough to read that well, but I'm passionate about it. Time, training, and experience will gradually get me to where I want to be.
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