What 7mm-08 load to try?

[roysclockgun]

I am disappointed in the performance of the new Howa 1500 7mm-08 rifle that I bought the wife. I have worked up loads, in the past, for all my hunting rifles over the years and have always gotten groups in the 1/2" area, or less, at 100 yards. This rifle, using factory Remington 140gr bullets and hand loaded Nosler 140gr. bullets, and Hornady 120gr. bullets, is doing no better than 2 1/2" at 100 yards. One 140gr. bullet appeared to keyhole into the target!
I do not have gauges, but the old bullet into the muzzle, shows the bullet sitting very high out of the muzzle, so the muzzle appears tight.
Thus far, I have used H380 and IMR4064. All very light loads, save for the Remington factory with 140gr. bullets, which did no better.
I went through the first 20 rounds, practicing the fire one and clean procedure. So, I know that I broke in the bore in the proper manner.
I have loaded up some 120gr. bullets, using Varget and will try again when the range opens on Tues.
If they do no better, I will contact Howa and see what they say. I hold an 01FFL, so I likely will get some positive response.
I used Weaver mounts and a Burris Full Field 3-9x40 scope. All screws have been checked for tightness, to include the receiver screws.
Any suggestions?
TIA
Steven in DeLand, FL

 

[onesonek]

Does that have that Hogue synthetic stock on it?
A buddy had one in a .30-06, and it took a lot of work to get it to shoot right.
It was a tad touchy in seating depth, but the wosrt seemed to be in the stock had too much flex.
I'll have to ask, but I ain't so sure he didn't end up restocking it.

 

[ScreaminEagle]

Mine loves IMR 3031 and 140gr Sierra Gamekings. Great combo on whitetail. Good luck

 

[bullet]

Use W760, H414, RL-17 and do not seat the bullets close to the lands give them a good jump. Hornady bullets will be a struggle to get good consistent group after group accuracy. If you are using a 140gr AccuBond make sure you seat it at 2.770" and that is where you start with COAL for all your hunting bullets you are trying. Hunting bullets need a jump to obturate properly and seal the bore for consistency. Good luck

 

[Guest]

It may be that the rifle just doesn't like light loads. I'd take a look at John Barsness' treatise on handloads that work:

http://www.loaddata.com/articles/PDF/Ha ... 20Work.pdf

Here's the excerpt on the 7mm-08:

7mm-08 Remington: You cannot
beat 47.0 to 50.0 grains of H-4350
and any bullet around 140 grains in
Remington’ s l i t t le update of the
classic 7x57mm Mauser. Some bullets are longer and grabbier so will
only take the lighter charge, but
Ho r n a d y ’ s 1 3 9 g r a i n e r wi l l t a k e
50.0 grains. Muzzle velocity ranges
between 2,800 and 2,900 fps in 22-
inch barrels.

I'd also look at the difference between flat-based and boat-tailed bullets. I've had rifles not shoot boat-tails but shoot flat-based spitzers into cloverleafs. I hope you get it worked out. I'm sure there's a sweet spot in there somewhere. I can tell you that many rifles like to be pushed, so the lighter loads you've been shooting may just not be "doing it" for the little 7mm.

 

[SJB358]

I am with Dubyam, work up a little with a little slower powder and see if that makes any difference. A good flat based PT would be excellent as well. Never can find fault with a 140 PT. My favorite 7mm bullet. Scotty

 

[bullet]

H4350 will not give you the velocities you would consider standard along with accuracy at the same time. Of course I could be wrong but in the three I have owned, H4350 would not give good velocities for my 7mm-08's. Also, you could have trouble with the Partition in getting real tight groups on a group to group consistent bases. Great bullet, one of the best on killing but not always the the most accurate. Of course if you don't take long shots then the kill area and placing a bullet right where you want to place it is not an issue.

 

[big rifle man]

If your not looking for barn burning speeds try H4895 with a 140 grain. This powder will give you 7X57 velocities for the most part, will drop whitetails quite nicely and in my rifle (model 700) prints 3/4 inch groups.

 

[roysclockgun]

Thanks for all the hints. I will try backing off the OAL, as the 120gr. Horn. Varmint bullet (flat base) that I wanted her to use for practice would close on 2.866" so I was backing off .006" to .012" and not getting good groups. Tomorrow I will try with backing off some more on the OAL.
I am still worried that the Remington factory 140gr. cartridges did not group better.
I will absorb all that has been written here and report after range tests tomorrow.
Best,
Steven

 

[onesonek]

Forgeot to add this earlier. While the crown may look ok to the naked eye,,,,the 140 gr. keyholing like that may be a fluke, but I would suspect the crown first off. 175 gr. I may suspect twist rate. But I would confirm with other bullets before doing anything both flat base and boattails.

 

[roysclockgun]

My error, but for many years, I believed that getting the bullet close to the lands was best.
I load the bullet in the case longer than I know will work. Coat the bullet with fiber tipped pen, and continue to "try" load, until no sign of the lands shows in the ink on the bullet. Then back off another .005". That generally works.
On this go-'round, I will take the advice and back off a bit more. The 120gr. flat based bullet closed on 2.866". I have backed off until all cartridges show an OAL of 2.829" to 2.839". Do you think that is enough? Or, that only range testing will prove it out.
Is this farther back OAL only because I am trying to work with light loads, or is it a general rule?
Since wife, Storm, was used to her .243Win., I want her to start off shooting the 7mm-08 with light loads and maybe, before Oct., work up.
The Howa rifle does have the Hogue, which appears to be rigid. I got the one with two stocks supplied. The barrel is free floated.
Steven

 

[Guest]

Steven, I think it's just a matter of finding the sweet spot in terms of OAL. I've not had much luck close to the lands in any of my rifles, but other do, apparently. Who knows why? I think you'll be fine. Just find a velocity you want and start playing with OAL in .010" increments. I wouldn't worry too much about how close to the lands you get, as your low-pressure loads won't spike over max, so maybe seating "wedged in" ends up being the best for grouping. It's always an experiment. What I can tell you is that in my experience, most powders don't like to be at low load densities. H4895 is apparently an exception to that rule. Experiment with whatever you have available, but I'd suggest H4895, H4350, or something in between those two in burn rate. Maybe Win748, as well, or Accurate 2520. It's all about finding the right combination, and so far, from what you're telling us, you haven't hit on it. Keep us posted.

 

[bullet]

Steven, I think it's just a matter of finding the sweet spot in terms of OAL. I've not had much luck close to the lands in any of my rifles, but other do, apparently. Who knows why?

I agree with dubyam, I have not found with 98% of the hunting bullets I have done load work for through the years that like being up close the the lands, but that is not the case with Berger VLDs, and some SMKs they seem to like it. You just got to do some load work. A trick that might get you there quicker is to use Sierra's OAL for any given weight bullet you use even though they are not Sierra bullets. You will find this medium, in the middle of the road seating depth will serve you well and you will not have to play as much with loads wasting bullets, powder and primers, much less brass life. Good luck and let us know.

 

[JD338]

I have loaded the 7mm-08 with the 10 gr BT and PT using RL 19. Accuracy was just under MOA.

JD338

 

[257 Ackley]

Best two powders I have found for this caliber are R15 and Varget. This is for 3 different rifles in this caliber.

 

[Powerstroke]

That's unfortunate to hear, as most -08's shoot what ever goes down the barrel fairly decent.

Early life, mine used a lot of IMR-4350 & 150gr SMK's and yes seated out as far as I could get them. Transformation turned over to the 150gr BT's with the same powder, but still under an inch....... this has remained constant with the 140's and 120's.

I think I will use strictly 120's in it moving forward, however I've also had great luck with N-140 powder - none of them have been barn burners for speed, but put the dot where it belongs and nothing has walked away from it.

 

[onesonek]

The 150 gr. NPT is still my favorite "all-around" bullet forthe .284/7mm chamberings.

 

[roysclockgun]

Doing what I was told to do here, I retested five loads, after setting the bullet back 2.829" to 2.840" OAL. I will need to do some more work, but here are the results, thus far, starting with the best group and working down. All were fired with 120gr. Hornady Varmint bullets, R-P cases and Herter's primers. All groups measured center to center:

1. IMR4064 39.1 grains = 5 rounds, 1 1/8"

2. H380 43.5 grains = 5 rounds, 1 7/16"

3. IMR4064 41 grains = 5 rounds, 1 7/16"

4. Varget 41.5 grains = 5 rounds, 1 1/2"

5. Varget 42.5 grains = 5 rounds, 1 1/2"

I had phoned the tech at Howa and he was not too helpful. The only recommendation that he had was to use factory Hornady cartridges using 139gr.bullets, which he claimed shot 3/4" groups in his 7mm-08. He would not discuss hand loads at all and was emphatic about that. He also did share that with factory reduced recoil cartridges, keyholing had been reported in the Howa 7mm-08 rifles. That answers one of my questions, because using a load one grain below the reommended, was where I did get one keyhole impact on the paper at 100 yards, during my first outing.

I think I now have some loads that I can work with. I only bought the Varmint bullets for the wife to practice with. Once I get the groups that I want, I will start with Nosler 120gr. BT and go from there.

Thanks for the helpful hints, regarding this issue. If you think of something else that might try, please let me know.
I also do need to lighten the trigger a bit!
Best,
Steven in FL

 

[bullet]

your over all lengths are to great. Work from these 2.780 -2.770 :mrgreen:

 

[SJB358]

Doing what I was told to do here, I retested five loads, after setting the bullet back 2.829" to 2.840" OAL. I will need to do some more work, but here are the results, thus far, starting with the best group and working down. All were fired with 120gr. Hornady Varmint bullets, R-P cases and Herter's primers. All groups measured center to center:

1. IMR4064 39.1 grains = 5 rounds, 1 1/8"

2. H380 43.5 grains = 5 rounds, 1 7/16"

3. IMR4064 41 grains = 5 rounds, 1 7/16"

4. Varget 41.5 grains = 5 rounds, 1 1/2"

5. Varget 42.5 grains = 5 rounds, 1 1/2"

I had phoned the tech at Howa and he was not too helpful. The only recommendation that he had was to use factory Hornady cartridges using 139gr.bullets, which he claimed shot 3/4" groups in his 7mm-08. He would not discuss hand loads at all and was emphatic about that. He also did share that with factory reduced recoil cartridges, keyholing had been reported in the Howa 7mm-08 rifles. That answers one of my questions, because using a load one grain below the reommended, was where I did get one keyhole impact on the paper at 100 yards, during my first outing.

I think I now have some loads that I can work with. I only bought the Varmint bullets for the wife to practice with. Once I get the groups that I want, I will start with Nosler 120gr. BT and go from there.

Thanks for the helpful hints, regarding this issue. If you think of something else that might try, please let me know.
I also do need to lighten the trigger a bit!
Best,
Steven in FL

Steven, it looks like your IMR4064 load is doing pretty well. The only other powder I would check out is the H4895. Hodgdon has youth loads using the H4895 that should be great for the 120's as well. Although, 1 1/8" with a new barrel isn't really bad. I still think your barrel is breaking in a little as well. A little tweaking on the 4064 loads should net you something useable. Any idea what those are running speed wise? Scotty