25-06 running slow?

[ksubuck]

I finally have time to really crunch the numbers from the past year of reloading. I had noticed my 25-06 seemed to be weak in the velocity department but wrote it off to a short barrel. I have an old Browning ABolt stalker with BOSS that has a true barrel length of 20 inches. When comparing my loads to what might be expected, I find them running 350 to 400 fps slower than the Nosler manual reports. Every combination from 85gr B-Tips, 110gr B, 115 PT/BT, 117 SST. Used Varget, IMR 4350, and H 4831. I know the guide reports from a 24 inch barrel. With the 4 inch difference I would expect a loss of 100 to 150 fps, not 350 to 400.

I bought this rifle used, it appeared to be in pristine condition. It dates from the late 90s so its been around for a while but it isn't ancient. Gunsmith scoped it when it arrived and said it looked good. No idea how many rounds down the tube. It is finicky when reloading but when you find a node it is sub MOA.

I haven't pushed any loads above book max, and see no pressure signs at book max. Measured case capacity on 10 once fired and neck sized cases, the average water capacity was 67.1 grains water so I don't think the chamber appears to be very oversized. The measuring the CBTO length of various loads they all fall right at 2.780 so the lands don't seem too far out. Starting to wonder where my pressure is going.

Anyone have any thoughts? I was planning on re-barreling the rifle if I wasn't happy with it. Was planning on a 26 inch Shilen light or medium varmint in 25-06. Is it time to re-barrel this winter?

 

[Guy Miner]

Interesting.

I'm a huge fan of the .25-06, and have found that my velocities are similar to what Nosler has published. Some a little higher, some a little lower. I do however have a 24" barrel.

Would not have anticipated such a large difference in velocity between your 20" and the 24" test barrel. I could live with 100 - 150 fps behind published figures, but the strength of a .25-06 is velocity. Without good velocity, I'm pretty sure that I'd either trade off the rifle or re-barrel it. I'm at a loss to explain the 350 - 400 fps difference you're seeing.

I would not over-load the cartridge to reach the velocity you seek.

Have never run a Shilen, but have shot against some in competition. They are high quality. Am pretty well hooked on my Kriegers though, and when I want a new barrel for my .25-06, I'll likely get buy a Krieger.

Regards, Guy

 

[Ridgerunner665]

From what I see...if 4831 is the slowest powder you've used, you're leaving about 100 fps on the table right there.

20" isn't anywhere near enough barrel...22" is OK, 24" is better, 26" is best.

I've heard some smiths won't work on Brownings...something about the threads and threadlocker.

 

[SJB358]

I'd run some RL22, 25, MagPro, Retumbo with the heavier bullets. I'm betting you'd still get 3000 or better with the 115's and 120's. I'm running 3140 with 120 A-Frames without leaning on it real hard.

 

[ksubuck]

I originally bought this rifle as a deer gun for my wife to learn to hunt with. She likes to shoot my 7 rem mag and her dad's 270 better. Who would have thought that she would overcome her recoil aversion so quickly...

I know many people will go over book until they see pressure signs. I guess I don't have the guts. I took one load in my life over max by a half grain to see if I could tighten a group up. It might have, but I backed down to max and called it good.

Think I will just plan on the 25-06 being this years project rifle.

 

[ksubuck]

I have some Retumbo on the shelf, so I will run a few groups to check velocities. If it remains consistently 350 to 400 off I expect to still fall short of 3000fps by a bit. If so, its a rebarrel. My smith laughed when I asked about ABolts. He says he is set up to deal with them, has dealt with them in the past, and has no fear. It is an older action with 20 tpi threads so it is a little more likely to gall. He said the worst thing that could happen is I would have to buy a m700 action and build a real rifle.

 

[1Shot]

I think it is your chrno. Yes you will loose some velocity with the 20" barrel but not as much as you say. I would check your chrno with some other rifles to see if they measure up then on the same day and set up shoot your 25-06 and she what you get.

 

[ksubuck]

The chrono measures velocities close to what is expected on other rifles. I did a series of temperature stability tests on a variety of loads in 4 different rifles on the same days. The other 3 rifles are spot on with what is expected. Wish it was the chrono.

 

[1Shot]

That is a head scratchier then.

 

[kraky]

The 2506 is alot like the 7 mag in the reloading data dept......there is alot of weanie data out there.
When looking at 115-120 loads for instance its not unusual to see 4 grains different among data w/re22 powder.
If you want to post some offending loads I or others can run it past quickload. Or feel free to pm me.
Once we know what you're getting for speed we can project some run ups.
I will bet right now you are more a victim of weak data than a slow barrel.

 

[Ridgerunner665]

Cartridge          : .25-06 Rem.
Bullet             : .257, 110, Nosler AccuBond 53742
Useable Case Capaci: 60.236 grain H2O = 3.911 cm³
Cartridge O.A.L. L6: 3.250 inch = 82.55 mm
Barrel Length      : 20.0 inch = 508.0 mm

Predicted Data for Indicated Charges of the Following Powders.
Matching Maximum Pressure: 61000 psi, or 420 MPa
or a maximum loading ratio or filling of 107 %
These calculations refer to your specified settings in QuickLOAD 'Cartridge Dimensions' window.
C A U T I O N : any load listed can result in a powder charge that falls below minimum suggested
loads or exceeds maximum suggested loads as presented in current handloading manuals. Understand
that all of the listed powders can be unsuitable for the given combination of cartridge, bullet
and gun. Actual load order can vary, depending upon lot-to-lot powder and component variations.
USE ONLY FOR COMPARISON !

80 loads produced a Loading Ratio below user-defined minimum of 85%. These powders have been skipped.
Powder type          Filling/Loading Ratio  Charge    Charge   Vel. Prop.Burnt P max  P muzz  B_Time
                                      %     Grains    Gramm   fps     %       psi     psi    ms
---------------------------------  -----------------------------------------------------------------
Norma MRP                           99.9     57.9     3.75    3100    98.9    61000   16711   1.014  ! Near Maximum !
Vihtavuori N560                    101.7     57.7     3.74    3091    96.1    61000   16869   1.008  ! Near Maximum !
IMR 7828                           106.2     57.3     3.71    3086    96.6    61000   16441   0.997  ! Near Maximum !
IMR 7828 SSC                       100.4     57.3     3.71    3086    96.6    61000   16441   0.997  ! Near Maximum !
Alliant Reloder-25                 107.0     59.1     3.83    3081    99.8    59276   16210   1.018  ! Near Maximum !
Accurate MAGPRO                    101.9     60.1     3.90    3075    94.5    61000   16859   1.016  ! Near Maximum !
Alliant Reloder-22                 101.9     57.2     3.71    3072    97.9    61000   16350   1.013  ! Near Maximum !
Winchester WXR                     104.6     57.5     3.72    3070    97.7    61000   16351   1.013  ! Near Maximum !
Alliant Reloder-17                  89.6     52.2     3.38    3063   100.0    61000   14972   1.010  ! Near Maximum !
Ramshot Magnum                     101.7     61.5     3.99    3056    98.5    61000   15746   1.007  ! Near Maximum !
Alliant Reloder-19                  98.8     54.9     3.55    3036    97.8    61000   15586   1.007  ! Near Maximum !
Hodgdon H414                        89.2     52.4     3.39    3035    99.0    61000   15330   1.013  ! Near Maximum !
Winchester 760                      89.2     52.4     3.39    3035    99.0    61000   15330   1.013  ! Near Maximum !
Ramshot Hunter                      94.4     54.1     3.51    3034    99.4    61000   15266   1.013  ! Near Maximum !
Norma URP                           94.0     51.6     3.34    3020   100.0    61000   14749   1.017  ! Near Maximum !
Vihtavuori N550                     91.3     51.8     3.36    3018    99.9    61000   14871   1.021  ! Near Maximum !
Norma 204                           93.8     53.8     3.48    3016    97.5    61000   15206   1.005  ! Near Maximum !
Accurate 4350                       93.2     51.7     3.35    3014   100.0    61000   14771   1.035  ! Near Maximum !
Hodgdon H4831 SC                   100.0     56.1     3.64    3010    95.8    61000   15269   1.003  ! Near Maximum !

 

[ElmerThud]

Results published in the manuals are as far as I understand obtained under controlled laboratory conditions using particular barrels with loads to SAAMI spec. Also published data may vary significantly from one propellant/bullet manufacturer to the other.

I cannot see how field testing using commercial chronographs will ever duplicate or match exactly those manual results published.

Your own tests using commercial chronographs will however give you a 'real time' look at what you are producing enabling you to utilise the information in terms of exterior ballistics for your own downrange use. Also allowing you to determine which of your loads is most consistent with other benefits too. Temperature will indeed also have an effect on the performance.

With a .25-06 as already mentioned, velocity is king & I find that case prep goes a very long way to achieving a correct neck/shoulder seal, therefore good pressure levels, when the cartridge is fired, with older un-aneald brass showing very poor performance. It's therefore much better to size to correct headspacing with good brass to get the best results.

The books generally say to allow 30fps for each inch of barrel lost or gained at 3000 or more fps & 25fps for less than 3000fps...

I tend to be happy with my 22" barrel if the Sierra 1620 100gn bullet is at around 3250fps MV and the 110gn AB at 3120fps MV both with low ES. Those are my own field test chronograph results.

Both bullets produce quick kills at ranges out to 250-300yds and for me, that's good enough.
Sorry, - not trying to teach anyone to suck eggs, just a note of my findings & hope it helps. ATB

 

[ksubuck]

Here is what I am seeing.

85g ballistic tips over 45.5g varget. Predicted with 24 inch barrel is about 3435. I am seeing 3151. Difference of 284fps.

110g AccuBond over 47.5g IMR 4350. Predicted around 3092. I am seeing 2713 for a 379fps difference.

115g ballistic tip over 51g H4831. Predicted around 3060. Seeing 2700 for a 360fps difference.

115g ballistic tip over 47.5g IMR 4350. Predicted around 3010. Seeing 2715 for a 295fps difference.

These are all the most accurate load for each load combination.

 

[Oldtrader3]

You are loading those bullets a little light in your .25-06. I am getting more velocity in my .257 Roberts then you are. Try some IMR 7828 SSC 55.0 for 120 grain Partition at about 3000.

I was using 50.0 IMR 4350 for 120 grain and 55.0 for 100 grain. Good luck.

 

[ksubuck]

These loads are middle of the road in relation to the published min/max. They are the most accurate in my rifle. The problem I have is as I run the charge up I lose accuracy. IMR 4350 at book max with the 115s shoots a cool 4 MOA. H4831 tightens it up to 3.4 MOA at max. Same story with 110 ABs and 85 BTips.

I have never had a rifle that is 3/4 MOA when you find a node but shoots all over the paper otherwise. I would love to have a rifle capable of hunting over 100 yards;-)

 

[Vince]

ksu,

My 25-06 is finicky.
It sounds like you have one that is similar. Mine runs Hornady 87 grain, 100 grain, and Nosler 100 grain bullets sub moa but everything else looks like a shotgun pattern. I've heard from others that due to the 25-06 being so overbore that it can be finicky and my experience seems to bear that out. Not only that but if I change the charge weights, like you, I go back to having great duck hunting loads that would make Phil Robertson proud.
I gave up on my 25-06 and just run the three loads it likes these days. Good luck to you on your rifle sir.

Vince

Sent from my SGH-M919 using Tapatalk

 

[ElmerThud]

"110g AccuBond over 47.5g IMR 4350. Predicted around 3092. I am seeing 2713 for a 379fps difference."

In my rifle- 20" barrel (22" inc breech dimension), with the 110gn AB I use 53gns IMR4831.
Fed210M primer and Lee Factory Die crimp. Gives approx. 3120fpsMV approx. 26fpsES

Same rifle using a Sierra 100gn Prohunter 1620 - 52.8gns IMR4350, Fed210M primer & factory crimp, approx. 3257fpsMV & not greater than 32fpsES

It's fair to say my barrel & its 1-10 twist really does not shoot heavier than 110gn bullet weights well at all. Having said that, I've shot stags at well over 300lbs with both the above bullet weights and loads without any difficulty arising.
My case head to lands measurement is: 2.915" and my comparator dimension is 2.870". So bullet ogive to lands is .045" freebore. That's the sweet spot seating for these two bullet weights & loads in my rifle.

Some target test results are shown below - all shot at 100yds.:
Please note the OAL dimensions shown are 'Comparator' dimensions and not the actual cartridge OAL.
I have some chrongraphed data on an xls file that I am unable to share here using various loads and the above bullets for .25-06

 

[Guy Miner]

There is much love for the .25-06 here on the forum, but I'm still at a loss to explain why your rifle is showing 300 - 400 fps difference between published velocities, and actual velocities.

Except barrel length. That's the obvious thing to blame... Though there may be other contributing factors like chamber dimensions, etc.

Funny thing, I've tried before, and attempting to stretch the barrel has just never worked out for me! :grin:

Re-barreling is expensive. If you REALLY like the rifle, then it's worthwhile. If you're not dead set on that particular .25-06, then use it as trading stock and try again.Before I settled on my .25-06 Rem 700 CDL, I also owned two other .25-06's:

Winchester Model 70 Sporter - Classic controlled round feed, nice dark walnut stock. Terrible accuracy. I spent about six months trying to get it to shoot rather than pattern, and sold it to a Winchester devotee.

Ruger Number One Varminter - I believe this was the most accurate factory rifle I've ever owned. Doggone one-holer with 100 grain Sierra soft point hunting bullets. But the heavy, varmint weight barrel was more than I cared for in the field.

Both rifles had their positive aspects, but neither was exactly what I wanted. Sold them and moved on. For the past ten years I've enjoyed what must be my perfect .25-06, for me.

Your present barrel is unlikely to ever produce the combo of accuracy and velocity you seek. Either re-barrel, or send the rifle packing. Those seem to be the choices. Once you've got a .25-06 that performs, you'll be content. It's a wonderful cartridge for deer sized game.

Regards, Guy

 

[kraky1]

OK....I checked your loads against quickload. It nails 3 of them on the head but is a little off on the varget load.
(And I think it might be burn factor problem with ql cause my guns all usually run hotter than quickload thinks with varget too)
Basically...quickload says you are running loads that are so mild you are barely above the pressure of a 3030!
I think you said you had a boss on that gun.....I think you need to get to work with some tuning...or perhaps you need to look at other bullets if you can't get these to shoot. And...its the loads that are leaving the velocity on the table. Heres what quickload thinks......

85 grain load 2941 fps at 43k pressure
110 load 2724 fps at 46k pressure
115 load h 4831 2695 at 46k pressure
115 load i4350 2704 fps at 48k pressure.

If it were me I'd be playing alot more with H4831 or some other slower powders.

 

[JD338]

Try RL22, RL25 and Retumbo.

JD338