Is my Lilja Chamber Throat Long & does it matter?

[BoxofRox]

If anyone has a Lilja barrel and some free time, can you try what I did and load a cartridge long, like at 2.45" and then keep stepping it down until it will chamber with the upper off of the lower and just pushing the bcg forward by hand? I'm genuinely curious if this barrel is cut too deep. I wouldn't assume these barrels should have over 150 thousandths of free bore from a standard coal.

[brut28481]

I think I'm having the same problem.

I was getting bad accuracy with my hand loads of 30gr, 30.5gr, and 31gr of CFE at 2.265 coal, so I wanted to find the lands. I started out by loading a round at 2.4" and seeing if it would chamber while I have the upper apart and just pushing the bcg forward by hand, and it did. So I loaded one at 2.45" and it wouldn't chamber. I kept shortening it by .005 until it would chamber and at 2.405 it finally did, but it was touching.

So with figuring my lands come into play at between 2.4 and 2.405 coal with a 123gr amax bullet, I loaded some up at 2.365 coal with the same 31gr of CFE I tried earlier with terrible accuracy. I single fed all of them and they chambered and fired fine. The velocity was an average of 60-70fps slower and the group size at 100yds shrunk in half, but is still over an inch. So now I have a problem, the bullet wants to be closer to the lands but there's no way I can load it there and still have a properly functioning AR.

Where do I go from here?

Also, measuring the ID of the necks on my fired cases, they're right around .272, that seems big.

Have you tried different powders? My lilja so far does not like CFE. XBR8208 has been the best with accuracy and velocity. ARCOMP grouped well but not as good velocity as XBR. I am going to double back on CFE with my longer COL. I also bought an ASC 6.8 Mag which is supposed to allow up to 2.31" COL.

Side note, went out today from 700-1090yds. After I figured the actual drops out (pretty close to StrelokPro with a G7 of .239) I was able to get easy repeatable shots with 5 rounds groups at 875 (5 in a row). Multiple hits @ 1090. AKA, once you get it grouping well, this barrel/round combo can go the distance!

[BoxofRox]

XBR is next on my list to try, but the fact that I can shrink my groups in half by running the coal out to 2.365, is kind of concerning.

[biodsl]

Given all my loads are around the 2.25 COAL, base-ogive= 1.65 (123 amax), that gives me a jump of 0.1! Seems way over most recommendations of 0.02.

Being new to reloading, I'm finding this fascinating.

I attempted to measure my new BHW .264LBC chamber for the 123 gr Amax. My average of 7 measurements is 2.378. An average for the Berger 130 gr AR Hybrid OTM is 2.399. Then I read this on the Berger website:

Many times the best seating depth is with the bullet touching or very near the rifling. However in some rifles, the best seating depth might be or more off the rifling. This is simply a variable the handloader uses to tune the precision of a rifle.

http://bergerbullets.com/wp-content/uploads/2013/03/COAL.pdf

[FW Conch]

^ Bingo ^ ;-))

[brut28481]

Being new to reloading, I'm finding this fascinating.

I attempted to measure my new BHW .264LBC chamber for the 123 gr Amax. My average of 7 measurements is 2.378. An average for the Berger 130 gr AR Hybrid OTM is 2.399. Then I read this on the Berger website:

Many times the best seating depth is with the bullet touching or very near the rifling. However in some rifles, the best seating depth might be 0.100” or more off the rifling. This is simply a variable the handloader uses to tune the precision of a rifle.

http://bergerbullets.com/wp-content/...13/03/COAL.pdf

Great Read!

[Klem]

Yes, good read.

When trying a new bullet the first thing I do is check how long I can load it to by using the Stoney Point gauge. In all 6.5G bullets measured so far the length of the magazine is shorter than the lands so that becomes the max COAL for all my bullets.

COAL may be an important variable in determining accuracy but I suspect there are more important variables, like barrel, bullet, powder and neck tension.

If you want to auto feed from the mag the shooters convention of loading out to .002" jump is impossible in my gun. Add to that anecdotal evidence of some long jumps being more accurate than shorter jumps and I think 'the shorter the jump the more accurate' tenet is a clumsy correlation. Like I said, there are more important variables, and if loading long reduces neck tension to less than the calibre (shank contact is less than 6.5mm), you are asking for trouble in an auto loader. Most long 6.5 bullets are fine with long shank contact but the 95VMax is not. Load this to mag length and there is less shank contact than 6.5mm.

One example I have is in 5.56mm. I load the 55gn Sierra SPBT (#1365) as a plinking round because it is the cheapest bullet I can find. Measuring in a Daniel Defence chamber when it touches lands is 2.405". This means the bullet shank has left the neck and is in free flight when it first touches the lands. I load these to 2.228 to fit in a mag and crimp them. Even though the jump is a huge 0.177" the round is averaging 0.9 MOA (4 rd groups) when bench resting.

I think jump distance is an accuracy variable but there are other variables that are more important, or are fixed.

[Klem]

If anyone has a Lilja barrel and some free time, can you try what I did and load a cartridge long, like at 2.45" and then keep stepping it down until it will chamber with the upper off of the lower and just pushing the bcg forward by hand? I'm genuinely curious if this barrel is cut too deep. I wouldn't assume these barrels should have over 150 thousandths of free bore from a standard coal.

I have listed the max-to-touch lands lengths for various bullets on Page 1 of this thread ('Max CAOL'). Mine is also a Lilja but they used a slightly different shaped reamer to your more recent purchase.

The Stoney Point (now called Hornady) gauge is a quicker way of realising when your bullets touch lands than using the method you describe. Both ways will achieve the same however.

[BoxofRox]

I have listed the max-to-touch lands lengths for various bullets on Page 1 of this thread ('Max CAOL'). Mine is also a Lilja but they used a slightly different shaped reamer to your more recent purchase.

The Stoney Point (now called Hornady) gauge is a quicker way of realising when your bullets touch lands than using the method you describe. Both ways will achieve the same however.

Dang, so your group buy Lilja is only 2.335 with the amax, and mine is over 2.4.

[Adam Lilja]

I recently acquired a 319 Lilja barrel and I'm seeing similar results. For comparison's sake I also nabbed up an AA 16" Incursion upper. As seen by others the Lilja barrel seems to do really well with 120gr PPU, however I tried some factory 123gr AMAX and SST and it didn't seem to care for either of them. The best SST 3 shot group I came up with was 1.680" CTC, AMAX averaged around 1" (which isn't that bad honestly), and the PPU average hovered around 0.5", best 3 shot group was 0.345". I went with 3 round groups due to having only one box of each type of ammo at the time.

I recently picked up a bunch of 123gr SMK's for reloading, and I've been trying to nail down a load for them for the Lilja. One interesting thing I wanted to share was I loaded an empty shell with an extended SMK at 2.366 COAL. I wanted to see how the cartridge chambered in both barrels comparatively. Surprisingly, the Lilja chamber gobbled it up and I was able to get a closed bolt that would fire. In the AA chamber the bullet was clearly hitting the throat way before I could even dream of getting the bolt in there.

So I'm not sure what reamer Lilja used for but I'm confident it's not SAAMI spec whatever it is, which is a bit disappointing. Necks on fired brass did measure out to either .2995 or .300 though, for what it's worth. My current running theory is that the Lilja throat is opened up for whatever reason, but it should work well with tangent ogive style bullets which is why the PPU runs so good in it.

By the way the AA upper absolutely hates the PPU.

We use Manson SAAMI spec reamers ONLY.

[Klem]

We use Manson SAAMI spec reamers ONLY.

Mine was from the original group buy which I understand was a not a SAAMI reamer.

[brut28481]

Update on a few items: I received go/no-go headspace gauges from reamerrentals dot com which confirmed the headspace is correct ie:, go gauge bolt closed, no-go gauge no bolt close. I suppose this further validates the throat of my barrel is somewhat longer and not from a headspace issue. I revisited CFE with the 123 A-Max as well and worked up some new loads with the Berger 130 AR-Hybrid. I was able to get both projectiles, when loaded to 0.05" jump off lands/COAL 2.30" utilizing the PRI 6.8 Mags, to shoot nice sub MOA groups with the Berger load actually having two shots virtually through same hole. I am very happy with this conclusion as I believe (haven't chronoed yet) the 123 Amax load @ 32.1 should be in the 2600 FPS range (the same load @ 2.25" COAL chronoed at 2650. I noticed a +/- 45 FPS drop from my XBR load @ 2.25" COAL when loaded to 2.32" COAL) and hoping the 130 Berger AR-Hybrid to be in the 2500+ FPS range. Both these loads will be great 1,000yd candidates. Interesting side note, I loaded the previously mentioned loads at 0.02" off the lands to begin with and the groups where much wider. Seems for me both projectiles with CFE liked to be off lands around 0.05".

[dammitman]

i gotta say i have never really understood why a revolver pistol like a ruger super blackhawk or actaully any revolver can hit anything with bullet jump to lands being .250-.750 on an inch. and yet i have seen good shooters hit targets over 100 yards away getting close to each other. oh not MOA for sure but offhand keeping 4 or 5 inch groupsand we worry about a few thousands jump in these rifles. whats up with that?

[brut28481]

i gotta say i have never really understood why a revolver pistol like a ruger super blackhawk or actaully any revolver can hit anything with bullet jump to lands being .250-.750 on an inch. and yet i have seen good shooters hit targets over 100 yards away getting close to each other. oh not MOA for sure but offhand keeping 4 or 5 inch groupsand we worry about a few thousands jump in these rifles. whats up with that?

Shooting 1,000+ yards at 18"x30" Steel plate.....1 Moa @ 100 Yards = +/- 1" spread. 1 MOA @ 1,000 yards = +/-10.5" spread. Sub MOA loads are going to give you a lot better hit probability at long range. In my experience thus far it takes a great deal of attention to detail to get your handloads shooting sub MOA, among all the other variables of gun/shooter.

[maxxmojo]

So I've finally been able to do a bit more testing with the 319 barrel I got. I had pretty good results from PPU and Federal, and I noticed with both of those factory loads the COAL was pretty short, in the 2.250 - 2.230 range. So on a whim with my latest batches I ran the COAL to 2.230 with the 123 AMAX bullets. I ran 31.4 - 31.6 grains of CFE223 today and the shorter COAL definitely shrank and tightened up the groups, before I'd get alot of seemingly random flyers. From what I can tell so far this barrel just seems to like the bullets jumping a bit, and I'm really happy to see I can make the Hornady pills finally perform. The 31.4 seemed to be the best load, with a 3 shot group of 0.615" at 100 yards. It was also the more consistent load at 600 yards, though I didn't measure the group size.