Browning B78 25-06 Problems with Nosler 110gr Accubonds

[Miguel Angel Camara]

Good morning forum,
I am having trouble developing loads for my 25-06 B78 Octagon Barrel, and would appreciate any advice,

Here's some preliminary data,
- Barrel 26", twist 1:10
- Job on the trigger by gunsmith, breaks clean & crisp.
- Job on forend, used to touch barrel, now it's floated.
Currently I am reloading,
- Neck Sizing just touching case shoulder, no feeding or extraction issues that I can see.
- 110 gr Nosler Accubonds,
- 53.5 gr of RL22
- Winchester Brass - now onto 4th reload
- Federal 210 primer.
- COAL 3.231""
- Jump to lands 0.015"
- AVG Muzzle speed - 2,940 fps,
- New Leupold VXII 3.5x10, nice and tight !
- Group size averages 1.5" @ 100 yd. (No vertical or horizontal stringing, nice constant triangles)
- Remington 120 gr Factory Ammo averages 2930 fps, so I can also assume no chronograph issues.
- Neck runout < 0.001"
- Bullet runout < 0.002"

NOTE: As soon as I arrived at 54 gr of RL22 I started seeing flattened and blown primers with past federal brass.
- I really hope I can get more accuracy and speed out of this 110 accubonds, I wonder if the bullets need to be pushed back a bit to relieve some possible initial pressure.
- I wonder given the 26" barrel length perhaps I should try a slower powder such as IMR7828 ?

Any advice will be most welcome as I would like to use this come next whitetail season

Thanks a mill in advance !

 

[243winxb]

The Twist Rate Stability Calculator said Your bullet is MARGINALLY STABLE. http://www.bergerbullets.com/twist-rate-calculator/

Plus looking at 3 different sources of data, 52 gr of RL22 would be my maximum.

 

[243winxb]

The calculator may be more accurate if the bullet length is measured from base to end of the jacket?? The plastic tip does make a difference, as its not lead or jacket.

 

[horsey300]

Try JBM calculator with JBM bullet length including plastic tip length

 

[243winxb]

Try JBM calculator with JBM bullet length including plastic tip length

http://www.jbmballistics.com/ballistics/lengths/lengths.shtml I got the length and run the calculator for JBM. Same results. Looks like a 9 twist would be better?

 

[Sunray]

52 grains of RL22 is maximum for a jacketed 115. 58 is max for a 100. Only Nosler lists a 110 and no RL-22.
I'd still look at a heavier bullet. Or use Alliant's 115 grain data. You use the 100 grain data?
"...with past Federal brass..." Federal brass is known for being softer than other brands. Blown primers etc likely just indicates the brass is too old. However, it could be the rifle too. That's very much a WHAG.

 

[Miguel Angel Camara]

Thanks all for your input, I feel I am going nowhere sticking to the 110 gr. Nosler AB
I will prepare some 115 gr Partitions of which I have plenty with RL22 and will certainly post updates.

I have also been told IMR7828 might be too slow for this combo, any thoughts ?

Here's a few pics of the primers using Winchester Brass, including a blown one.
I lack experience diagnosing primers, I would love to hear some comments. Primers used are Federal 210.

This is the max load I reached using 54 gr of RL22 with the 110 gr Nosler AB
This is the only Winchester case I've had problems with, but using Federal brass I had a few more instances.

I am seating the bullets 0.010"-.015" from the lands, could this be an issue ?

Again, many thanks all for your input.

 

[LoonWulf]

Something is suspect here, not sure what it is, besides possibly over worked brass. Google turned up a number of threads about it on other forums over the years. 54grs is likely hot but shouldnt be blowing primers, velocity should also be in the 3100fps or better range.

 

[JimKirk]

I have also been told IMR7828 might be too slow for this combo, any thoughts ?

IMR 7828 works very well under the 110 gr Nosler AB as does Retumbo ... Retumbo gives slightly higher velocity, but I like the IMR 7828 a little better .... it is my go to load for deer....

http://load-data.nosler.com/load-data/25-06-remington/ for Retumbo

 

[JimKirk]

Try a different brand brass .... I get flat primers quicker with WW brass over Remington or Federal .... don't know why ... but it happens for me ....

 

[Muddydogs]

Well if FedEx would deliver my scope today like they initially indicated I would have been able to report how my Savage shot the 110 grain AB with Re22 out of PPU brass but since they changed the scope delivery date to Saturday it will be another week before I get to the range. I've got my test rounds set .010 off the lands, the brass is new so its full length sized for the test run but it will be interesting to see how much difference it makes once I shoot some brass that just has the shoulder bumped back.

 

[horsey300]

http://www.jbmballistics.com/ballistics/lengths/lengths.shtml I got the length and run the calculator for JBM. Same results. Looks like a 9 twist would be better?

I think accubond is just longer than most people are used to, fusions are comparatively stubby. 9 twist may be needed. Partitions are shorter as are prohunters (sierra) should allow for more case capacity to level out the pressure signs, I can't seat 88 bergers at the same depth as 87 hornady bthps or 85 Sierra anythings because their length gobbles up case capacity, increasing pressures, reducing accuracy and velocity, if you don't want to give up on a marginally stable bullet, see if your pressure issues go away, play with the depth. I go Max magazine tolerances when I can, but on my single shot 223 from Cva, I just seat em as long as I can without jamming them into the lands. I neck size too, are you using a collet or something else? Too much neck tension could be a problem too.... I've seen pressure signs on mid-range loads due to the tension problem here and there.

 

[horsey300]

Accubond is 1.195" and hornady 120 HP is 1.185" closest comparison I could find, if you have a hornady book check their data on that bullet and compare.......nosler shows RL19 on their full lineup of .25-06 pills......I know lotsa ppl swear by rl 22 in this cartridge, but just a thought....

 

[243winxb]

The Twist Rate Stability Calculator said Your bullet is MARGINALLY STABLE. http://www.bergerbullets.com/twist-rate-calculator/

Plus looking at 3 different sources of data, 52 gr of RL22 would be my maximum.

http://forum.accurateshooter.com/threads/browning-b78-25-06-reloading-tips.3912121/ Oop, gas leak, primer fail. with photos.

 

[Clark]

I just built a double pillared fore end for a B78 25-06, took it out in the sage brush and sighted it in at 50, 100, 200, 300, 400, and 500 yards. That rifle could have done 600y, but I was working on 5 of mine and 3 of others for hunting.
I was using 51.5 gr IMR-4451 115 gr Nos Bal tip moly 3.25" nos brass, 3185 fps chrono

 

[JimKirk]

With that long 26" barrel ...I would at least give the very slow powders a try RL26, IMR7828, Retumbo, H1000 HV-100...
My 22' Browning A Bolt can safely get 3150+ fps with the 110 gr AB with either IMR 7828 or even more with Retumbo....

I have been reloading the .25/06 since 1969 and have tried many different(not all by any means) powders .... the slower ones just work in this cartridge...

Read this link to see where the .25/06 is placed on the overbore charts .... overbore cartridges are better suited with slower powders..... http://www.accurateshooter.com/technical-articles/overbore-cartridges-defined-by-formula/