quote:

Originally posted by maladat:

Do the JLK bullets live up to their published BCs? The numbers are certainly impressive.

The 6.5 130's did not live up to the generous BC for me.

quote:

Originally posted by maladat:

Do the JLK bullets live up to their published BCs? The numbers are certainly impressive.

The % who say they do to the % who say they don't is at best 60%, at worse 35%. I tried 200 pieces in a 6mm, and they did not hold a candle to the Bergers. All in all they took about 90 rounds to tune, far more than any Lapua, Berger or Sierra I have ever tried. Most people's biggest complaint is they make hens teeth and 4 leaf clovers look abundant.

quote:

Originally posted by offgrid:
Hang your steel from a single point, you'll get the feedback you need to help you figure out what the wind is doing.

If you need any conveyer belt drop me an e-mail, have a bunch of it I got free.

The following is from today at the family ranch.



I currently have only 3 pieces of steel - 12" square, 8" square, 5" circle. In this picture the squares were on fixed mounts on t-posts and the circle is hanging from your t-post, hose clamp, and rebar setup.

Swinging steel is definitely easier to see and hear. .308 is a bit "energetic for the 5" circle out to 300 yards -- the furthest out I shot today. The .308 completely spun the target in a 360 degree loop. .223 did 180 degrees at most, and then only at 100 and 200 yards. This setup just may work OK for my 700 yard station with a big piece of steel.

Accomplished today:
- Setup and marked shooting stations for 100, 200, and 300 yards from this berm. I still want to find a 400 yard station to complement my initial 470 yard location.
- Developed dope for my ARs at 100, 200, and 300 yards for 9400' DA.
- Confirmed that regarless of twist (1/9, 1/8, or 1/7), my ARs like FGMM 69. I have not yet run the numbers in JBM, but it sure appears that SMK 69 bucks wind noticeably better than Hornady's 55 VMax bullet.
- Final shots of the day were at the 5" circle steel from 300 yards with a 16" 1/9 twist carbine sporting 5x max glass. Three hits in a row with FGMM 69. I figured it was time to pack it up and go home.

FWIW, with exception of a couple shots into weeds (no dirt splash), I saw every impact in my scopes at 300 yards. I even saw a few impacts at 200 yards from my scope. My technique isn't good enough to see 100 yard impacts -- maybe someday....

I'll keep you posted on your offer for conveyor belting. I'm OK for the steel I currently have, but I suspect I'll be order more soon.

quote:

Originally posted by fritz:

I'll keep you posted on your offer for conveyor belting. I'm OK for the steel I currently have, but I suspect I'll be order more soon.

Ya, you can never have enough steel! I'll be in Denver quite a bit this month for work, glad to meet up with you somewhere.

quote:

Originally posted by maladat:

Do the JLK bullets live up to their published BCs? The numbers are certainly impressive.

I have experience with only two of his bullets; the 80gr ,224 and the 180gr .308 with the long boat tail. For those two, the claimed BC was very close. I have never tried the 6, 6.5 and 7 versions.

One thing to keep in mind is that these bullets are very long and the recommended twists from Swampy are insufficient in my opinion. I've always been a faster-twist guy, without going overboard. In Bryan Litz's new book, he does talk about the impact of slower twist on the BC of the bullets. He says that using a twist that yields a stability under 1.5 causes the bullet to have its BC degraded and I think a lot of people shoot these long bullets out of rifles with marginal twist rates. and leave BC on the table.

For instance, JLK recommends 1:12 as the optimum twist rate for the .308 LBT. JBM shows the stability factor for that bullet to be 1.44 with a 1:12 twist at 2800FPS in 90degree weather. This is the velocity I get with my 32 inch barrel. With my 1:11 twist the stability is 1.715. The same bullet in a 24 inch barrel at 70 degress will have a stability factor of 1.35. Litz says you lose between 3 and 5% of your BC for every .1 under 1.5. He also says you may gain some going above 1.5, but that's not something that happens all the time.

Moral of the story here, make sure you get a stability factor above 1.5. So choose your twist wisely, but don't go overboard.

Also, these bullets may be somewhat difficult to tune as you have to jam the bullet in the lands and not a lot of people measure that and keep chasing them over time.

quote:

Originally posted by offgrid:

Mark Chanlynn is a wealth of knowledge for sure. Been making barrels and gunsmithing for 43yrs, High Master High Power shooter....I'm finally going to use one of his barrels on my next barreled action.

He recommended 8.5 twist with his barrels and I went with it. Look forward to trying it out.

Thanks for all the comments on the JLK bullets.

If I start reloading 6.5 Creedmoor I may have to check them out. The Hornady factory match ammo is good enough and inexpensive enough that I haven't been feeling very motivated to start reloading for it.

quote:

Originally posted by maladat:

Thanks for all the comments on the JLK bullets.

If I start reloading 6.5 Creedmoor I may have to check them out

If your chamber has been throated for 140 Amax's, might not have the bearing surface in the neck touching the lands with the JLK's. Not pooping on the JLK's here. I know the JLK 130's are substantially shorter from the base to the ogive compared to the 140 Amax's.

quote:

Originally posted by offgrid:

quote:

Originally posted by maladat:

Thanks for all the comments on the JLK bullets.

If I start reloading 6.5 Creedmoor I may have to check them out

If your chamber has been throated for 140 Amax's, might not have the bearing surface in the neck touching the lands with the JLK's. Not pooping on the JLK's here. I know the JLK 130's are substantially shorter from the base to the ogive compared to the 140 Amax's.

That's an excellent point. I get my barrels chambered using a dummy cartridge with a JLK bullet seated exactly how I like it seated and then chase the lands from that point on. My .308 cartridges are right at 3.0 inches long.

That said, the A-Max is a great bullet at a very affordable price.

(Fixed spelling.)

This message has been edited. Last edited by: NikonUser,

Good point on the chamber throat. If the JLK bullets like to be touching the lands I may be out of luck using them.

If it wasn't already totally obvious I am not a super-experienced long range shooter, it will be now: I'm actually not sure exactly how my barrel is chambered. I told the folks at APA I mostly wanted to shoot the 139-142gr bullets but might shoot 120s or 130s sometimes and let them decide how to chamber it.

The VLD designs are ones that you can safely have bullets jammed into the lands. This is not something you want to do with non-vlD designs unless the manufacturer recommends it.

You can always seat the bullets longer or shorter to fit you needs.

As for me, my match rifles are chambered to that the bullet seated with the pressure ring just above the junction of the neck and the shoulder is where I want to start. They I chase the lands by seating progressively (very slowly) longer until I swap the barrel out (along with the brass.)

I developed addtional prone shooting stations at our family ranch. I now have 100, 200, 250, 300, 350, 400, and 470 yard stations for the main berm. Being a total sheep dip this morning, I didn't bring the .223 data book. I progressed out from 100 to 400 yards, confirming elevations for both the 18" and 24" barrel ARs. The following impacts were from 350 yards, just before repainting, and just before an hour long electrical storm. Mongo don't shoot in the prairie during lightning.



The left plate is 8" square and was shot with the 24" AR with FGMM 69. High at 11 o'clock was shot #1. Down a click -- shots #2 and #3 still at bit high at 12-1 o'clock. Down another click. Three shots at center to 9 o'clock, less than 1/2" vertical dispersion. Yep, got dope.

The right plate is 12" square and was shot with the 18" AR with FGMM 69. Guesstimated the elevation correctly from the get go. Three shots at center to 9 o'clock, less than 1/2" vertical dispersion. Dope again.

Today's breezes were from right to left before the storm, and left to right after the storm. One of these days I might eventually see calm and/or consistent wind. Or not.

How you mounting those plates to the stakes??

quote:

Originally posted by entropy:
How you mounting those plates to the stakes??

If those are from JC Steel...there's a piece of angle iron vertical, welded to the plate that the steel attaches to. Top of the angle has a triangle welded in to close the hole. Allows you to simply drop the plate onto a t-post.

I've got a 8" square by 1/2" thick and it has held up VERY well.

quote:

Originally posted by FN in MT:

quote:

Originally posted by entropy:
How you mounting those plates to the stakes??

If those are from JC Steel...there's a piece of angle iron vertical, welded to the plate that the steel attaches to. Top of the angle has a triangle welded in to close the hole. Allows you to simply drop the plate onto a t-post.

I've got a 8" square by 1/2" thick and it has held up VERY well.

entropy -- FN in MT is correct, those are JC Steel T-post brackets. JC's brackets come in 4 sizes to fit a number of plate sizes. JC's brackets have slot holes rather than fixed bolt positions, therefore each size is adjustable for slightly different bolt spacing distances on the steel plate. The brackets are burly and they hold the steel quite well. On the downside the steel's resonance is changed -- I get a duller "thwack" instead of a distinct "ting" of a free hanging plate. Also, there's virtually no movement of the plate -- you must see your hits.

Big Dog Steel also makes a T-post bracket. BD doesn't not have the adjustability of JC, but it does allow the plate to swing a little. BD's design gives the plate a bit more resonance and some visual cues from plate swing.

In the FWIW department for those of us who shoot factory ammo:

Hornady's AMax, ZMax, and TAP 168 grain ammo all seem to be the exact same in flight characteristics. At 400 yards in 8500' DA, they all required 6.25 MOA elevation. All three showed minimal vertical dispersion (1" max for 5 round strings) and similar lateral dispersionn for wind.

Black Hills' 168 AMax appears to be loaded a little cooler than Hornady -- it required 6.50 MOA elevation for the same conditions. I've seen this tendancy of BH ammo being a bit slower than others in precision rifle courses, where BH's version of FGMM requires a click or three more elevation than FGMM.

Hornady's 168 BTHP also required 6.50 MOA in the same conditions. It's my understanding that the 168 BTHP bullet has a slightly lower BC than the AMax bullet, so the additional elevation makes sense.

Bottom line -- all five loads are quite accurate in my GAP rifle.

quote:

Originally posted by fritz:

Bottom line -- all five loads are quite accurate in my GAP rifle.

You buy your rifles at The GAP? My daughters shop there a lot; I'll ask them to pick me up a rifle next time they go there.

This message has been edited. Last edited by: NikonUser,

quote:

Originally posted by NikonUser:
You buy your rifles at The GAP? My daughters shop there a lot; I'll ask them to pick me up a rifle next time they go there.

I actually prefer shopping at Victoria's Secret, but I'm...well...in between sizes. So I defaulted to GAP.

I see. You're "special."

Long distance + wind = learning experience.

I was in northeastern Colorado today with the .308, shooting Hornady factory ZMax 168 grain (aka AMax/TAP). Shot like dog doo-doo from 100 to 300 yards, then finally woke up and eliminated most of my cranial-rectal inversion as we moved out from 400 to 1000 yards. The remants of a monster rain storm from last night, plus two substantial storm cells today led to switching winds.

One woo-hoo moment of the day was hitting a standard IPSC steel plate {18" wide by 30" tall) at 1,150 yards. It took 2 shots to determine elevation dope, then hit 5 for 8 of the remaining rounds. Shots #4 through #10 were virtually on the same elevation, which meant the rounds held vertical well and I mostly had my head out of my backside. Wind holds on hits were all the way from 7 to 13 MOA left of center, depending on wind strength. Considering that the target was only 1.5 MOA wide, I was holding WAY left of center.

Every day, every shooting range is different. I have much to learn with wind calls.