Filter

Firearms Craddock Precision Bartlein 6.5 cm Lr308 / AR10 upper Complete BRAND NEW

Here’s what I have. Never had a round in the chamber. Entire upper is 100% BRAND NEW
- Craddock Precision Bartlein 6.5 Creedmoor 22” barrel .875 @ gas block +3 rifle gas bead blasted and marked Craddock Precision Bartlein 5r 6.5 barrel $765
- Aero M5 upper reciever $175
- SLR Sentry 8 detect adjustable gas block $150
- Sgt of Arms 17.5” ARCA Handguard $240
- Terminator brake $220
- Rubber City Armory HP Bolt carrier group $300
- Vltor BCM charging handle $100
$1940 invested minus tax and shipping
Selling for $1725
I’ll include a new POF 308 roller cam pin $25
As well as 2 extra HP firing pins $80
Thanks for looking
Cross Listed
Text for further info 815-343-3888
IMG_5026.jpeg
IMG_5025.jpeg
IMG_5024.jpeg
IMG_5023.jpeg
IMG_5022.jpeg
IMG_5021.jpeg
IMG_5020.jpeg
IMG_5019.jpeg
IMG_5018.jpeg
IMG_5017.jpeg

Neck Tension Inconsistencies on Lapua 6.5CM Brass

The first 45 bullets were out of one box of lot #1468 of Berger 220s. Then I ran out of bullets and had to open a new box of lot #1468 of Berger 220s. Nothing else changed. Same brass prep, same press setup, same time, same everything. Literally, all I did was get up, walk over to where all my bullets are, retrieve a new box of the same lot, and continued seating.

I contacted AMP to get their perspective and the first thing they said was, "measure the bullets."

Unfortunately, I had taken those last 45 bullets out to the hills the weekend before. Fortunately, if you want to call it that, one of those rounds had a bad primer. So, I pulled that one bullet and compared it to a few bullets out of the new box.

What I found:
- The OAL was essentially the same.
- The body of the bullet was ~.025" longer on the new-box bullets - measured by putting a comparator on both ends of the bullets.

Looking at the graph, you can see that the new-box bullets engaged around .025" earlier. That makes sense if the body is longer. You can also see that the slopes of the graphs are essentially the same. The reason the terminal forces on those bullets is higher is that there is more bearing area. In fact, if you just slid the orange plots to the right, they would match up.

EDIT: Morale of the story, measure your bullets every time you open a new box.
Apparently, when you refer to the "body of the bullet" you're referring the the Bearing Surface.

Several years ago now, I discovered this difference in bearing surfaces between lots with two different lots of 168 SMK's where there was a difference of .033". So I sorted through them and set aside 20 that were .033" longer than 20 of the shorter. Loaded all 40 up and shot them into 10 round groups and chronoed all the shots. As I thought there might be, the .033" longer bearing surface rounds had a very different average velocity and a very noticeable difference in POI at only 100 yds.

Like you, I discovered it's a good idea to sample measurement for every new lot/box of bullets as there can be significant differences. But I'll point out too that the difference in bearing surface length being quite small, like .010" or less, isn't really going to show up on target or in velocity due to all the other noise that's going on.

Opinions on VV N540 powder for 223/5.56 hand loads?

N540 is pretty good for heavy 223s. Give about an extra 25-50FPS over varget for the same pressure out of my 77TMK loads, accuracy was similar, tad worse than varget but SD wasn’t as good.
I was loading 25.0gr for a bolt gun load at 2.475in with the 77TMK. Lapua brass, CCI 450.
Apparently it reduces your throat/barrel life faster than N140 and Varget.

Accessories TBAC CB muzzle devices

Selling a bunch of TBAC muzzle devices
1/2x28 brakes - $80ea shipped
5/8x24 brakes - $80ea shipped
1/2x28 non timed brake - $80 shipped
1/2x28 flash hider (unfired) - $100 shipped
CB thread protector (unfired) - $25 shipped with another muzzle devices
Ecco machine hub mounts for CB - $60ea shipped

Attachments

  • 20250401_104312.jpg
    20250401_104312.jpg
    1.7 MB · Views: 15

Optics Nightforce NXS 5.5-22x56 MLR

IMG_7122.jpeg
IMG_7140.jpeg

Nightforce NXS 5.5-22x56 MLR - $1500 shipped

More Pics

This scope is used, but it very good condition. Glass is perfect and everything functions perfectly, just shows typical normal cosmetic wear from use. This has MRAD turrets w/ 5 mils per revolution. It includes the original bikini cover, paperwork, and microfiber — as well as a sunshade, which does show some wear around the edges.

Discreet PayPal F&F or Zelle preferred

7-08 vs 7 SAW vs 7CM vs ? for Large Frame

iu


After the War, Army Ordnance and Fort Benning wanted a smaller COL than M2 ball (.30-06), but with the same performance. So they shortened the case to something similar to 300 Savage and increased the chamber pressure, added a boat tail to retain energy resulting in the T65 and later 7.62x51.

If they had done the same thing with the .450” case head .276 Pedersen, we would have had something with a 2.400 to 2.600” COL, running higher pressure in the M14, FAL, G3, and AR-10.

Velocity differences between 6.5cm brass brands

I appreciate the feedback. I expect some change but some of the numbers just seemed all over the place.

I would like to be able to load an assortment of headstamps so they get close to the same velocity with a particular bullet but it just doesn't seem achieveable. Some brass gives tighter SDs, some is overworked and is disposable, some I have more of for when I need to load up for a match so I different uses for them.

I am trying to keep tabs on everything by recording velocities and putting them in a spreadsheet where I record the day's weather, powder/primer/bullet/case type and number of loadings.
I think the best you can do when mixing headstamps is to measure each case's cases volume/capacity (not weight) and that should be a close as you can get for consistent velocities between them. Keep in mind there are other issues going on, like differences in the thickness and the alloy composition of the brass that'll react differently to the expanding gases as well as sizing which will effect pressure/velocity. It's simply best to stick to one headstamp of the same lot at a time. Otherwise, it just get complicated. ;)
  • Like
Reactions: Rodney65