Desired CBTO problems

[Texas10]

From your post is sounds like the rifle is new and never fired by you, so it is possible it was not chambered correctly. But if you have shot a factory load like a 75 gr Hornaday, tell us how that worked out.

Here is a sanity check to compare to your measurements. With an empty case, seat your chosen bullet long and chamber the round, pushing on the bolt to force the bullet into the case. When I do this I seat the bullet in the case, remove it and seat again to lessen neck tension for this check. You may have to tap the seated bullet/case out with a cleaning rod to preserve the seating distance as it may stick horribly.

Measure the CBTO of this fully jammed bullet seating. This will tell you the longest CBTO you are going to be able to load, but be aware that extracting a loaded round seated this long may result in the bullet being stuck in the barrel. Nevertheless, this information is useful.

Next, neck or FL size the Hornaday modified case and seat a bullet .010 shorter than your jam measurement just taken. Mount the case on the tool and slide it up the chamber with a firm push, then attempt to retract it. If it sticks, the bullet is in the lands. You don't use the gray plastic rod in this step, so you can remove it entirely if you wish.

Remove the tool and the case from the tool and seat the bullet an additional .010 deeper and keep repeating this test until there is no tendency to stick upon retraction. Once you're there, seat the bullet just .002 shorter than the last measurement where the bullet still had a tendency to stick and work your way shorter until you can feel it just wanting to almost stick. You can withdraw slightly, rotate the case in the chamber and test again to get a good feel for where exactly the lands are. Sometimes the case is slightly banana shaped, the bullet is slightly askew, or the neck is slightly off axis with the case body, all these will become obvious during this test and result in a dragging feel during retraction that is not to be confused with the feel of the bullet sticking in the lands.

That is your touch dimension. If you are still ending up with the ogive of the bullet right at the case mouth, you've got a short chambered barrel. Return it, or have it throated deeper.

Let us know what this test results are.

 

[Ned Ludd]

Throating a barrel longer when the bullets are already seated out to maximum mag length is not a good idea. It will accomplish nothing for rounds that are confined to being loaded to mag length.

 

[South Pender]

The Hornady tool is pure junk....

Is there a better tool that operates roughly similarly to the Hornady?

 

[270 ftw]

Is there a better tool that operates roughly similarly to the Hornady?

Its the method as much as the poor quality of the tool. The video that zero333 posted above is the way to go and you dont have to spend money on a tool.

 

[divingin]

Next, neck or FL size the Hornaday modified case

I would advise against this. The case is a standard piece of 223 brass which has been drilled and tapped through the primer pocket with a 5/32-36 thread. This leaves precious little metal supporting the rim in a case like 223. What you'll find is that, even with a liberal dose of case lube, you'll tear the rim off pulling the case from the sizing die (don't ask me how I know. Or why I own a 5/32" x 36 tap.).

If you're going to monkey around with sizing and seating and not use the tool, just strip the bolt and use a spare piece of unmodified brass.

 

[Texas10]

I neck sized the Hornaday LNL modified cases, maybe that's why I never had a problem ripping the head off, although I can't imagine a case that's already SAMMI sized would get stuck in a die. I'll have to give it a try, i guess.

 

[grovey]

Team,
Thank you all for all your replies and those who took a lot of effort in their replies. I will be back out in the reloading shed again this weekend with a couple of ideas. I think the first action will be to re measure the chamber making sure that I play around with the feel as I push the projectiles forward and make that I am not getting false readings. When I did my first batch of 20 measurement I had a shortest of 1.750 which at the time I put a ? next to, and the longest as 1.815 which I wrote "rammed into lands?" In total there were 3 measurements in the 1.81* so I am now thinking that there lays the answer.

Dave

Have you made back to the reloading shed yet?

 

[Howland]

You cant stop sliding the dinky plastic rod on first resistance. What happens is the bullet starts heading in there slightly nose down due to the loose fit between bullet and neck on the modified case. So you start to feel freebore area rubbing on the bullet and your still miles away from the actual measurement you're going for. Try using a lot more pressure on the rod and hold the main piece of the tool with your other hand so it doesn't start to back out. Then tighten the little set screw down really firmly cuz that plastic will slide right over the screw if its not super firm.

Given what you have described, there are a few possibilities. The first is that you may not actually be pushing the bullet all the way to "touching the lands with your Hornady OAL gauge.
-------
The first time I tried to determine distance to touching in the first of these rifles with the Hornady OAL gauge, I pushed the bullet in until I felt the "touch", then tightened the set screw and pulled it out for measurement. To my surprise, the bullet was seated pretty far down in the case and the measured COAL was much shorter than I thought it should be. Turns out, it was almost exactly 0.169" shorter than it should have been because the "touch" I felt was the bullet contacting the leading edge of the very tight freebore, NOT the lands. Once I figured that out, I re-measured with the Hornady OAL gauge, making sure to give a harder push with the plastic rod. Sure enough, with a little more pressure, I could feel the bullet "slide" in farther from the initial light "touch" until a true hard "touch" at the lands was reached. The tight freebore gave the false impression that the bullet had reached the lands.

Thanks guys. Trying again and using just a tad more force gave me very consistent measurements. 2.987" CBTO just kisses the lands in my magnum RPR.

... but loading to mag length is a 0.080" jump.

... but first time at the range turned in a .543 MOA group best at 200 yards

... but at a very modest 2,400ish fps.

I used H1000, 215M, virgin Lapua brass and 285gr. ELD-M.

 

[PHINPAD]

Team,

I did indeed make it back into the shed at the weekend and I took the measurements again. It is with some embarrassment but also relief, I can report that with forcing the rod forward I was able to get some much more consistent readings which did show the chamber to be longer than I was originally working to.
Previous average was 1.773", new average is now 1.860" Quite some difference.
If they load I include two pictures taken with the rod inside the Ruger Precision Rifle. Due to the stock design it is quite difficult to turn the brass locking knob. A longer design would work much better but I don't know if there is a market for it.
Again, thank's for all your help.

Dave