25-06 running slow?

[ksubuck]

No offense taken. I am really appreciative of the help. It isn't an A.I. chamber.

I have a lot of new Win brass that I have prepped and started using. So, I do have measurements of new versus once fired cases. Base diameter goes from 0.463 to 0.464. Mid body diameter from 0.453 to 0.458. Diameter at shoulder from 0.437 to 0.438. Neck O.D. from 0.281 to 0.291. Length from base to shoulder 1.942 to 1.950. Length from base to neck 2.191 to 2.192. Is that much of a change?

What happens to the QL data if you shorten the barrel to 20 inches? This rifle has a BOSS which they include in the advertised 22 inch measurement. But if you check true barrel length from bolt face to crown of the barrel, it is really 20 inches.

 

[ksubuck]

Also, I am using H4831. That may change things a little.

 

[Dwh7271]

At 20" adjusted for your velocity it looks like this:

Cartridge : .25-06 Rem.
Bullet : .257, 115, Nosler BalTip 25115
Useable Case Capaci: 60.111 grain H2O = 3.903 cm³
Cartridge O.A.L. L6: 3.250 inch = 82.55 mm
Barrel Length : 20.0 inch = 508.0 mm
Powder : Hodgdon H4831 ?

Predicted data by increasing and decreasing the given charge,
incremented in steps of 0.389% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-03.9 98 52.86 2847 2070 54427 14692 95.5 1.078
-03.5 99 53.08 2860 2088 55131 14755 95.7 1.072
-03.1 99 53.29 2872 2106 55845 14817 95.9 1.065 ! Near Maximum !
-02.7 99 53.51 2884 2124 56568 14878 96.1 1.059 ! Near Maximum !
-02.3 100 53.72 2896 2142 57300 14939 96.2 1.052 ! Near Maximum !
-01.9 100 53.93 2909 2161 58043 14998 96.4 1.046 ! Near Maximum !
-01.6 101 54.15 2921 2179 58795 15058 96.5 1.040 ! Near Maximum !
-01.2 101 54.36 2933 2197 59558 15116 96.7 1.034 ! Near Maximum !
-00.8 101 54.57 2946 2216 60331 15173 96.9 1.027 ! Near Maximum !
-00.4 102 54.79 2958 2234 61114 15230 97.0 1.021 ! Near Maximum !
+00.0 102 55.00 2970 2253 61909 15286 97.2 1.015 ! Near Maximum !
+00.4 103 55.21 2983 2272 62714 15340 97.3 1.009 ! Near Maximum !
+00.8 103 55.43 2995 2291 63530 15395 97.4 1.003 ! Near Maximum !
+01.2 103 55.64 3007 2309 64357 15448 97.6 0.997 ! Near Maximum !
+01.6 104 55.86 3020 2328 65196 15500 97.7 0.991 !DANGEROUS LOAD-DO NOT USE!
+01.9 104 56.07 3032 2347 66046 15551 97.9 0.985 !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 5% powder lot-to-lot burning rate variation using nominal charge

 

[Dwh7271]

I'd be interested to see how a load around 54.6 gr works in the rifle. Should be right around a node at that loading based on what you're seeing.
Don't know if you've found a seating depth thats working for you yet but a couple loads at that and around it high and low would be interesting I would think. Depth I used in QL is 3.25" which is the default.
I also realize that it is not the speed you really want but may tell you something.
Looking at H4831, you really can't get to the next OBT node. Barrel time on a 20" is around .924 and that takes you into the danger zone deeply IMO.
Another item that occurred to me, (you probably already figured it) if usable barrel length is 20", you're probably not going to get traditional 25-06 speeds out of it. Depending on what you hear, 20-50 fps loss per inch versus the 24 to 26 inch barrels. Figure if Guy is getting 3050 or thereabouts, 20 fps loss comes out to 2970 (which is where your 55 gr load is) or 50 fps puts you around 2850 or so. My point in that is maybe the speeds you are seeing are a little closer than you think?

 

[ksubuck]

The 54.0 load was most accurate of the string at 0.8" and 55.0 was in at 1.1". 54.5 was 1.7" May have had a flier that I didn't notice. Not that I look at the targets again, the 54.0 was a triangle, the 54.5 was two in one out, and the 55 was two touching with one out. Will focus there and see what I find.

OAL of 3.250 put me at 0.050 off the lands and is where I have been working. Will do some seating depth work soon as well.

 

[Dwh7271]

I'm sure you know this, but the 54 or 54.5 loads should be in the sweet spot or close.
I agree with shortening it a bit. Probably bring that one out right in.

 

[Guy Miner]

Figure if Guy is getting 3050 or thereabouts, 20 fps loss comes out to 2970 (which is where your 55 gr load is) or 50 fps puts you around 2850 or so. My point in that is maybe the speeds you are seeing are a little closer than you think?

I'm running 115's at 3120 fps, or 3190 fps, depending on the bullet. Have been using Retumbo with the 115's for a number of years now. That's with a 24" factory barrel.

Guy

 

[Oldtrader3]

My grandson has a Browning A-Bolt Stalker from 1995. This rifle used to belong to me. USRAC only made the BOSS A-Bolt Stalkers in .280 from 1995 to 1997. His is a 22 inch barrel behind the BOSS, 24 inches with the BOSS? I do not believe that you can get 3000 fps with a 150 grain bullet from a 20 inch barrel? My 140 gr handloads used 58.0 grains of IMR4350 @ 2950 fps in that rifle. He killed a 350 pound hog in Texas with that load (one shot).

 

[Dwh7271]

I'm running 115's at 3120 fps, or 3190 fps, depending on the bullet. Have been using Retumbo with the 115's for a number of years now. That's with a 24" factory barrel.

Guy

Whoops! Sorry Guy, I shorted you on speed. No harm intended. :grin:

 

[Guy Miner]

I'll get over it. Sniff, sniff, snuffle... Callin' my rifle slow... sniff... :mrgreen:

 

[ksubuck]

Time to wrap this thing up. Repeated and finalized the load. 54.0g H4831 it is. Chrono 2915. 0.8 MOA.

I appreciate everyone's help. I have learned quite a bit from this thread. QuickLoad is interesting, this rifle should harvest deer at short and intermediate range just fine, and I will rebarrel it someday soon to experience the true 25-06.

 

[Dwh7271]

That's much better than it was.
Remember, you're probably only working w 20" or so of effective barrel so nothing wrong w 2915. .8 works also.
Glad it worked out for you.