Author Topic: 7-08 accuracy (Read 1346 times)

super mario · « **on:** August 14, 2009, 01:21:47 AM »

Ok I got a 7-08 barrrel for my nef. I put it on and it fits perfect, locks up nice and tight. Went to the range and its not shooting very well.
I used 140 gr rem core locks. Just when I think its going to hold a pattern it starts shooting left or right or up or down. If I had to say it is holding a 4" group.
I pulled the barrel and put my hornet barrell back on and put five around 3/4" with 3 being about 3/8".
Put the 7-08 back on and same thing, its all over the place. I do handload for the hornet, havent loaded for the 7-08, not yet. I now have some brass to work with though.
Where should I begin on this thing, try a new scope first or try a different load.
What has worked in ya'lls 7-08

quickdtoo · « **Reply #1 on:** August 14, 2009, 05:06:08 AM »

I'd start with the barrel fitting info in the FAQs, just because it seems to fit well doesn't mean it fits right, latch engagement needs to be checked. After that is right, use the accurization tips in the FAQs.

Tim

lonewolf5348 · « **Reply #2 on:** August 14, 2009, 02:45:30 PM »

My 7mm-08 like IMR 4350 and it was 43.0 grains behind 139 sp Hornday bullet.I did from the bench at the 100 yard target 1 1/2" 3 to 4 rounds.
I did notice the gun did not favor bullets close to the lands more like a max: 2.810
I think there was room for improvement but I did switch back to my 30-06

super mario · « **Reply #3 on:** August 14, 2009, 03:21:21 PM »

how do you check the col.
Tell me if this will work. I took a spent case put a very slight crimp in it with my teeth and pushed a bullet into it leaving it long, I pushed it into the chamber all the way then pulled it and measured it. Did it several times and came up with the same numbers.
with a 120 gr BT it measured 2.88, and with a 139 gr it meausured 2.83. I loaded some up minus .05 which is only 2.78 on th 139's.
If that is correct that might have been my problem with factory 140's being at 2.80, thats awfull tight, no?
I am trying varget and win 760 in different amounts working up, in loads of 5
I checked the barrell, space is good and latch is good.

lonewolf5348 · « **Reply #4 on:** August 15, 2009, 12:57:44 AM »

you got it, the only problem .05 off the lands you may spike pressure if using high end loads.
I would start with 2.800 and see how the groups turn out and then increase the COAL maybe 15 thou at a time.

gendoc · « **Reply #5 on:** August 15, 2009, 01:31:07 AM »

i had simular problems with a customers barrel..
it would not perform with factory ammo. about 6 different brands and flavors.

started using nosler spec handloads and it turned into a tack-driver
using 150gr bt's, and partitions with 39.5gr imr-4895. new brass and cci mlrp
col-2.800 2709fps this load is .5gr below max. you need to start with 36gr and work up.

also must let barrel cool between shots.

44 Man · « **Reply #6 on:** August 15, 2009, 01:43:59 AM »

It still sounds like something is loose. I would think that a bad factory load would still shoot a couple of inches at 100 yds, with that gun. I'd check fit, forearm, scope mount, rings, and scope, in that order. What scope do you have on it? Usually Rem core locks will shoot as good as any hunting ammo out there. Good luck with it, I hope you get it shooting to your satisfaction. 44 Man

gendoc · « **Reply #7 on:** August 15, 2009, 01:51:30 AM »

yes 44man, you could be right...
but have you ever checked consistancy of factory ammo grain weight
of powder and projectiles.. much less col.
i have read many articles about ammo manufacturers these days..
super-mass production for the demand

super mario · « **Reply #8 on:** August 16, 2009, 09:13:10 AM »

My buddy had a 7-08 in a Rem sps. It shot the same way using coelocks, I was thinking his gun was a POS but this has me thinking that maybe its the factory ammo. he sold that gun. Before you ask, yes I can shoot. This same day my buddy was trying out a used 300 mag he bought, he got it sighted in and was doing ok, I did a 3 shot group with it that were touching, roughly a 3/8" group. Like mentioned earlier I did a 3/4" 5 shot group the same day also with the Hornet barrell on it.
So where should I start off the lands for col. I already loaded some up with .05 off the lands, that makes my 139 gr at 2.78 col

gendoc · « **Reply #9 on:** August 16, 2009, 09:24:18 AM »

please describe the bullet your using, other than 139gr.
what powder and charge?

Lefty Dude · « **Reply #10 on:** August 16, 2009, 10:04:42 AM »

Several years ago I bought some Remington 30-06 factory ammo on sale during the hunting season. I shot some in my Browning 1895 lever rifle. The ammo was so bad I could not get it to group in 50 yards. And it slung shots all over the target. No consistancy at all. I finally gave it away it was so bad.
I can see why it was on sale and so cheap. IIRC, it was like $7.99 a box of 20.

Thats the last factory ammo I bought. I have been rolling my own for 40 years. Nothing beats a custon hand load, tailored for a specific firearm.

gendoc · « **Reply #11 on:** August 16, 2009, 10:24:09 AM »

quote...

"Thats the last factory ammo I bought. I have been rolling my own for 40 years. Nothing beats a custon hand load, tailored for a specific firearm."

thatsa what ima talk'n bout...

super mario · « **Reply #12 on:** August 16, 2009, 11:40:04 AM »

Quote from: gendoc on August 16, 2009, 09:24:18 AM

please describe the bullet your using, other than 139gr.
what powder and charge?

I loaded up 120 gr's as well.

I want to see if it likes 120's any better.
Anyway so far what I have done is this.

120 gr Nosler BT-- Win 760 48 gr and 50 gr--COL---.05 off the lands= 2.82
120 gr Nosler BT--- Varget 43 gr and 45 gr--COL---.07 off the lands = 2.80
139gr Hornady btsp interlock---varget 40 and 42 gr-----COL .05 off the lands = 2.78
I havent loaded up any 139's with the win 760, looking for load data on it.
Probably go to the range tommorrow, PS I whacked a 90lb boar last night with my Hornet.

gendoc · « **Reply #13 on:** August 16, 2009, 12:06:45 PM »

try your loads that you have and see if any difference..
unfortunatly, i don't use w760 or varget for any of my handloads.
the nosler spec is great info... try loading some to 2.800 col
i don't think i have ever seen a handi with a less than spec chamber depth,
more likely a larger one...

my 08 likes 160gr nosler partitions with imr-4895

i tried some lighter weight bullets a few years ago, and they never did much justice.

i like heavy stuff............

w760 and varget is a little slower burning than the imr4895, they should be a good choice

try your new loads and see.... OH-YEAH!!! GOOD JOB WITH THE HORNET!!!!!!!!

lonewolf5348 · « **Reply #14 on:** August 16, 2009, 12:21:05 PM »

I just went out to the reloading bench and to ccheck what spec: I had left on my 7MM-08 barrel and it seems your chamber depth is a lot shorter then mine was.
I remember 139 hornady remington brass my COAL that the chamber will close on was 2.880
I also remember the 140 noslers were at 2.870
seem your spec: are a lot different then my barrel was I wonder why?

gendoc · « **Reply #15 on:** August 16, 2009, 12:22:26 PM »

mario, have you checked your cartridge length before loading? should be 2.035
did you smoke your projectile before checking the depth?
insert bullet into cartridge by hand, a little long... use a lighter, and smoke the bullet and insert and close
the action.. of course no powder, or primer in the cartridge!!!

i just had to say that cus someone would come-unglued about that recommendation!!!

the lands will appear quite well on the smoked bullet

quickdtoo · « **Reply #16 on:** August 16, 2009, 12:32:33 PM »

Quote from: gendoc on August 16, 2009, 12:22:26 PM

have you checked your cartridge length before loading? should be 2.035

Make that case length should be 2.035", trim length is 2.025".

Tim

quickdtoo · « **Reply #17 on:** August 16, 2009, 12:38:03 PM »

FWIW, I'm into the lands on my 7mm-08 at about 2.750"- 2.800" depending on what bullet I'm loading.

Tim

gendoc · « **Reply #18 on:** August 16, 2009, 12:39:04 PM »

dang tim... i've been wait'n fer ya to show up!!!

gendoc · « **Reply #19 on:** August 16, 2009, 12:51:32 PM »

case to me means... gun case, case of beer, court case. but most of all

bad case of loose'n it... which is me!!!

super mario · « **Reply #20 on:** August 16, 2009, 01:15:11 PM »

what does smoking the bullet do, I mean whats it going to tell me, aint I after total length.
I did trim the brass to spec.

gendoc · « **Reply #21 on:** August 16, 2009, 01:34:09 PM »

it will tell you how deep your chamber is before the lands.
sometimes people do this and see markings on the bullet, and it could possibly
be touching anything... the lands will show up evenly around the bullet..
mic it to the markings, it will get you close.. do it several times
or you can purchase a depth gauge

super mario · « **Reply #22 on:** August 16, 2009, 02:20:45 PM »

I smoked a bullet, I did the 139 gr interlock
overall I came up with 2.83 again and to the land its 2.21
So what does this tell me

44 Man · « **Reply #23 on:** August 19, 2009, 01:25:38 AM »

Just make sure you seat your bullet at least .005 shorter than where it is touching the rifling. But I really doubt that your seating depth is your culprit. A bullet seated against the lands will raise pressure. Seated WAY off the lands will degrade accuracy. This degrading will only affect the guys who are after the last little 1/4 " of accuracy, nothing that would affect the kind of problem you are having. I would try other bullets though. I have a 7-08 comming soon and I certainly hope I don't have trouble like this. You might consider sending it back to H&R and letting them check it. 44 Man