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Discussion Starter · #1 ·
I don't have a Chrono yet; however, it is definitely next on my got to have reloading tools list.

So......I was wandering if there is a "rule of thumb" as far as barrel length vs velocity is concerned. Right now, I'm loading 180grn Sierra Game Kings on top of 57.5grn of IMR 4831.

The Sierra load manual shows this combo at 2,800 fps out of a 26" barrel. My 30-06 BAR has a 22" barrel. Is it possible to "ball park" estimate fps out of a barrel 4" shorter than the load manual barrel?

Thanks!

firstshot
 

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firstshot,
Very hard to quantify, but with a slow powder like that, prolly around 100-150fps. I've been using my Chrony a lot lately, a PIA to set up, and to record the data. But well worth the effort in terms of the knowledge as to what's goin' on! Working up some loads in 356Win, 38-55, 45/70, and 348,all new cartridges for me. With the incredible range of powders available I've made the decision to stick with just the one brand, Alliant.
Very comforting to shift a 'gear', one powder speed to another, and find that velocities are performing as predicted.
The next level would be some of the pressure test equipment that's out there, but certainly knowing where you're at in terms of muzzle energy helps a LOT.
Cheers,
R*2
 

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Discussion Starter · #3 ·
Rrusse11

I was just guessing it would put me in somewhere between 2600-2650 so I wasn't too far off. Reloading without a Chrony is kind of like reloading blindfolded. I've just got to get one so I'll know where I'm at.

I've found a great load for my 30-06 BAR with the Game Kings & IMR-4831 but I just don't know where I'm at velocity wise. When working up the load I shot 12 groups of 3 starting with 62 grns. The lowest two charges grouped a little over an inch @ 100 yds. Out of the next 10 groups 7 of them were sub MOA & the other three had flyers that were no doubt my fault. Got a good hunting load here, just need to find out where I'm at on velocity.

firstshot
 

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firstshot,
Case in point happened at the range two days ago. Speer #13 lists max load of 40gr of Rx7 with a 180JFP doing 2358fps. Just so happens I got a bunch of Nosler Silhouette 180grainers, with a flat point. Non expanding, lol, though I'm gonna do some penetration tests. 38gr of Rx7, and I'm seating them long, I've modified my 336ER's action for more COAL, gives me 2340 with lovely consistent ballistics.
It's a pistol bullet sized to .356, but with the nose just engraving in the rifling, it shoots great!
So 5% under their max load is giving me the same velocity,,,,,,no pressure signs, and I could prolly push it a bit faster, but I'm starting to nail the 200 yd target, have to hold a lil high,,,,,, but damn satisfying outa' a 20" barrel lever action. About 2" high at the 100yd and right on the money at 25 and 50 yds without touchin the sights. I started goin' from one to the other as an exercise in getting a feel for ranges and POI.
One of those great moments when you stumble on a load that shoots.
The first 5 shots went into 1 ragged hole at 50 yds. I shot the other 5 thru the Chrony as well,,,,,, and went home and loaded up 2 dozen and made it back to the range that evening. {:eek:). Ayup, it still shot!
Cheers,
R*2
 

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Discussion Starter · #5 ·
Rrusse11

You're absolutely right about finally finding a load that shoots great. I had shot about 150 rounds of Nosler Ballistic Tips, tried both 180grn & 165grn and could never get them to group well no matter what powder charge I tried. The 180's grouping between 1.5-2" and the 165's between 2-4". I was really focusing on bench technique and simply couldn't do any better than that. I was starting to doubt my shooting ability and was dang sure doubting the accuracy capabilities of the gun.

Then....bingo / bango....I find the the magic load and all of a sudden I've got one of the most accurate guns in the world and I'm a great shooter....LOL. I guess this is a good lessen in confidence, patience and determination. I knew I was a better shot than that, but still started to doubt my capabilites. The same with the gun. I knew that Browning BAR's were supposed to group better than that, but was almost ready to trade it in on something else. Boy am I glad I didn't!!!!

It just goes to show you that some guns like certian ammo better than others. You've just got to be patient and determined enough to find out what it is.

firstshot
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Make your first shot count!
 

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firsthot,
I hear ya! I got a Browning 78 in 22-250 with a lovely fine reticled old Weaver K10 on it that when I get discouraged, or doubtfull, I pull that out. Take a short walk,,,, then can usually put 3 into an 1" at a 100. I only got one of those plastic front rests with a bag of shot, but figger that gettin' any more involved is too much trouble. Them miroku build rifles are beautifully put together, and they shoot!
Cheers,
R*2
 
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