New Berger .224 Bullet

[1911mag]

I will start testing in about a week
Bartlein 5R 1:7 finished at 31", ISSF reamer on new Borden HBR action.

 

[Ned Ludd]

They are shooting pretty good at 3025fps out of a 32" bbl.

Longer barrel - not surprising. I was specifically referring to a .223 Rem with a 30" barrel to make a point that whatever greater velocity you might be able to get above the velocity at which a load actually tunes in is meaningless if you can't hit the next accuracy node without killing your brass in a single firing.

 

[Ray Gross]

Longer barrel - not surprising. I was specifically referring to a .223 Rem with a 30" barrel to make a point that whatever greater velocity you might be able to get above the velocity at which a load actually tunes in is meaningless if you can't hit the next accuracy node without killing your brass in a single firing.

My apologies if I offended, that was not my intent. I've heard that people are running into pressure at lower velocity and I just wanted to point out that some folks are getting the 85.5s to run well in the high 2900s/low 3000s.

The extra 2 inches of barrel won't account for the extra ~175 fps additional velocity.

At first I thought the pressure issue might be due to the freebore length difference between the ISSF chamber at .169 vs the Manson Fullbore chamber at .200. The ISSF seeming to show pressure sooner vs the Fullbore that I'm using, but that does not seem to be determinative either. A couple weeks ago at a local club match, I was able to chronograph a friend's load. He's running very close to the velocity that I am, with a free bore length that is approx .100 shorter in a version of the Wylde chamber. (And doing it with .9gr less powder). He is showing pressure signs, I am not.

I have eight firings on Lapua brass and the primer pockets are just now beginning to loosen. Not a single one of those cases show any brass flow into the ejector cut.

 

[Ned Ludd]

No offense taken at all, just clarifying that I was referring in the previous post to a specific scenario with a 30" barrel. The 2" additional barrel length won't directly account for a 175 fps increase in velocity. In fact, I wouldn't expect it to be worth more than 20-30 fps at the very most. Increasing the freebore length will also make a small difference in the pressure required to achieve a given velocity, but again, not nearly enough to account for a 175 fps increase in velocity. So how are you actually achieving those velocities with the 85.5s without killing your brass?

As noted, using a slightly longer barrel and/or lengthening the freebore are two ways to achieve a given velocity at slightly lower pressure. I have previously played around with the 85.5s in QuickLoad quite a bit. Even inputting a 0.220" freebore, a 32" barrel, and running up the pressure to ~57.1K psi, which is comparable to the 90s @ 2850 fps over H4895 from a 30" barrel, the best predicted velocity for the 85.5s is around 2950 fps. Once the program has been calibrated, I have found the predictions I get from QuickLoad to be very good. So again, I'm curious how you're getting an additional 50 fps beyond that velocity (or more) with the 85.5s, together with 8 firings on your brass?

I can certainly think of a couple ways you might be able do it, including using some other powder besides H4895, or moly-coating bullets, but most people's loads with the 85.5s using Varget or H4895 in Lapua brass are not going to reach anywhere near 3000 fps without major primer pocket issues. If there's some secret or special approach involved, you don't need to let the cat out of the bag, as I'm just curious and have no intention of attempting to replicate your results. Nonetheless, you seem to be getting far greater velocity than most, so it seems like a question worth asking.

 

[Ray Gross]

Try N140.

I'm curious what your bore and groove diameters are.

 

[Bamban]

They are shooting pretty good at 3025fps out of a 32" bbl.

I am confused, we chrono my buddy's molied 85.5 ammo at 2885 with LabRadar, his terminal velocity at 600 is higher than yours with muzzle velocity at 3025. eTarget not calibrated right?

 

[XTR]

3000+ and brass that isn’t smoked doesn’t make sense. The velocity numbers on the target don’t match either. A quick JBM calc shows that 600 yd velocity (1957) running in the range of 2880ish depending on atmospherics. @iron308 what chrono did you use.

 

[Ned Ludd]

Come on you guys. Maybe he just doesn't want to give out the secret sauce. 2880 fps, 3025 fps, what's the diff? All I know is that the Lapua brass I use in a 30" barreled F-TR rifle throated long would withstand one of those two velocities, but would be "one and done" at the other. But that's just a plain Bartlein 5R barrel without any secret sauce.

 

[Bamban]

Ned,

Here is the reamer I used on the ELDs, it works real well on the 85.5s as well. Note dimension "N" I am not really a good fan of the 45 degree cut in front of the neck. When we laid down the angle we did not change the effective freebore of 0.140.

Only used it on ARs for across the course. It still runs well with mag length 77s. No idea how good it will be for the bolt guns.

Thoughts?

 

[Ned Ludd]

I'm not sure what you mean by "effective" freebore. The reamer shown above cuts a freebore of .072" (i.e. 0.0723" U & V). That seems pretty short to me, but I'm only running bolt guns with bullets like the 85.5 and 90 VLD. Where is the 85.5's boattail/bearing surface junction in relation to the case neck/shoulder? If it wasn't doing double duty with the 77s, I'd want a chamber for the 85.5s to have a minimum of around 0.130 to 0.140" fb. However, the most important question is how does it shoot? If it shoots well, a lot of "theoretical" optimal parameters fly right out the window. It's surprising sometimes how far from what is theoretically "optimal" it is possible be an still have a setup that shoots great.

For example - I have a custom .223 bolt rifle I had built some time ago as basically an F-TR "trainer". At that time, I wasn't reloading and so didn't specify the chamber dimensions or buy my own reamer. When I got the rifle back, it shot one ragged hole groups with FGMM77s, so I was pretty happy. Later, I wanted to work up a load with the Berger 80.5s and got the reamer print from the smith. I found out the rifle had "zero" freebore. Despite being far from ideal, I was able to work up a load with the 80.5s that shoots quite well. However, the bullet is sunk way down below the neck/shoulder junction. Think "Journey to the Center of the Earth" deep. LOL. So it is certainly possible to load a long heavy bullet with a relatively short freebore, but you will generally be running pressure higher than is necessary for a given velocity. I'm not really certain how long a freebore you could go with using the 85.5s and still seat the 77s without jumping them a country mile. Nonetheless, if the chamber cut with the reamer above is working well for you, I wouldn't change a thing.

 

[Bamban]

When you lay down that 45 degree cut down to 10degrees, you eat some of that 0.140 freebore. What shown is what's left of it, but from dimension "T & V" you will see the full length.

 

[Ned Ludd]

When you lay down that 45 degree cut down to 10degrees, you eat some of that 0.140 freebore. What shown is what's left of it, but from dimension "T & V" you will see the full length.

The T & V dimension includes the empty space from the end of the chamber neck diameter out to the start of the actual freebore, or lead. Technically, that is not freebore, but now I understand your use of the term "effective", as it will certainly have an impact on how far down in the neck the bullet will be seated at a given seating depth. Thanks for clarifying.

Along that line, with bullets seated at something like .010" off the lands, where will the 85.5's boattail/bearing surface be in relation to the case neck/shoulder junction? Just curious. In the example I gave above, I was able to get away with seating the 80.5s so far down in the neck by using H322, which is a faster powder than I would ordinarily choose for that bullet, but it has very small kernels and a high bulk density, and so did not run into any issues with a compressed load. Regardless of where the 85.5 is seated in the neck in that chamber, it doesn't sound as though you are running into the issue of a compressed load either, so the freebore it cuts must be sufficient.

 

[Bamban]

I understand. Compare the T&V on other reamer, you will see what that typical difference is with U & V. From there you can extrapolate what that 0.140 represents.

 

[Bully]

@55fairlane

 

[1911mag]

Better late than never - new set up done and fire formed 200 rounds with LC brass. I am doing all different on this one. Turned and sorted brass to .5g , used Federal Match primers, H4895 (firsts all the way around) started at .005 off lands today. Now results are only at 100 yds and next is repeating to 300 yds.

group at top is 5 shots and lab radar results
Granted this is a tad slower than @Ned Ludd has previous posted of a sweet spot.

 

[Highpower-FClass]

1911mag, if you don't mind, what powder charge and jump? and is that a 28 or 30 inch barrel?

 

[1911mag]

Don’t mind at all
31” Bartlien 1:7
I settled in with 23.2 for my choice to shoot group today.
.005” jump was my starting point
Granted this is first round of tests and 300 and 600 will tell me more. I ran 88 Atips to fire form and was shooting 1/4 minute with that at 300.

 

[xswanted]

Don’t mind at all
31” Bartlien 1:7
I settled in with 23.2 for my choice to shoot group today.
.005” jump was my starting point
Granted this is first round of tests and 300 and 600 will tell me more. I ran 88 Atips to fire form and was shooting 1/4 minute with that at 300.

Curios if you think a guy could get this same velocity with a 24" 223AI?

 

[Ned Ludd]

Better late than never - new set up done and fire formed 200 rounds with LC brass. I am doing all different on this one. Turned and sorted brass to .5g , used Federal Match primers, H4895 (firsts all the way around) started at .005 off lands today. Now results are only at 100 yds and next is repeating to 300 yds.

group at top is 5 shots and lab radar results
Granted this is a tad slower than @Ned Ludd has previous posted of a sweet spot.
View attachment 1173652 View attachment 1173653 View attachment 1173654

I and a couple other guys I shoot F-TR with have been running the 90s in the 2775 fps range over H4895 from a 30" barrel (Lapua brass). They shoot VERY well there. I'm guessing you're hitting the same node. I have been using that load for fire-forming brass, and will boost it up to the 2840-2850 fps node once that is all finished. The other guys are using it in matches and doing very well with it. The difference in performance (windage @ 600 yd) between the two loads is fairly small, and the slower node apparently doesn't kill Lapua brass 3 to 4 firings (or less). Looks like you've got things dialed in nicely!

 

[Ned Ludd]

Curios if you think a guy could get this same velocity with a 24" 223AI?

The .223 Rem AI case provides only a modest increase in capacity over the parental .223 Rem case. My guess is that you'd be asking a LOT from one to get that velocity from a barrel that is 6" shorter AND without killing the primer pockets pretty quickly. You'd certainly also want to have sufficient freebore to load the long bullets.

If you want to see how fast you can tune the 90s with a .223 Rem AI setup and a 24" barrel, I'd suggest starting with brass that has a thicker case head than Lapua that may be able to withstand the increased pressure a little better. You could easily do some preliminary testing and find out there was any chance it would work, but I wouldn't push it if it didn't look like it could get there.