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SHOOTIST357
12-17-2017, 08:57 PM
standard 336W in 30-30

165 gr cast with 19gr of 4895 --nice groups other than the cold bore shot.

Help me out -- This gun will shoot nice groups every time except for the first shot. and you never know where that first shot is gonna go, but it will be 4" from the cloverleaf group at 25 yards. any ideas?

SHOOT

OS OK
12-17-2017, 09:25 PM
About the only thing I can think of to pull that cold bore shot down into the group is Boron Nitride...http://www.autofixinfo.com/8DUSLHoWPhYsD5/Tubb-Precision-Blended-Boron-Nitride-Coating-Kit.html

Tubb's been working on this for years.

Bird
12-17-2017, 09:43 PM
Sounds like the bore is too clean rather than cold. Don't clean the bore and that may eliminate the first shot problem. I gave up cleaning the bore after every outing.

john.k
12-17-2017, 10:35 PM
A fouled bore has more drag and causes the slow powder to burn evenly........go for a quicker powder.

trails4u
12-17-2017, 10:48 PM
Funny things....rifles. I have an old Rem742 in 30-06. The ONLY predictable slug down the bore is the first. When I used to hunt with it, I always prayed I didn't need a follow up shot....cause it could go 8" in ANY direction after the first. :)

OS OK
12-18-2017, 08:03 PM
Funny things....rifles. I have an old Rem742 in 30-06. The ONLY predictable slug down the bore is the first. When I used to hunt with it, I always prayed I didn't need a follow up shot....cause it could go 8" in ANY direction after the first. :)

Did you ever figure out why it did that?

FergusonTO35
12-18-2017, 09:06 PM
What sort of velocity and usage are you trying for? 19 grains is awfully light for 4895, although Hodgdon recommends it for reduced loads this doesn't mean it is optimal for such usage. 28 grains gets 1750 fps out of my 336T with a Lee C309-150-RF and I'm planning to bump up the charge some more because I think that will be more accurate. Does your rifle have micro groove? I find my Marlins shoot best with a bit of fouling. I think this helps the bore to grip the boolit better and, as John K. suggests, helps powder to burn more thoroughly. In any event, I would try a stronger charge or a faster powder before I did anything else. If you want velocity in the low 1000's (which I suspect 19 grains of 4895 is producing) then something really fast like Unique would probably be a better choice. It is much less position sensitive too.

trails4u
12-18-2017, 09:23 PM
Did you ever figure out why it did that?

No....I never did, and eventually gave up. I didn't give up easily.....spent a lot of time and components on load development trying to find a sweet spot, but I never found it. Even researched and did all the 'tricks' to supposedly accurize a 742. I think I eventually got it to about a 4moa rifle...but no better. It's an old rifle, with many, many rounds down the tube, and as a 742 it was never inherently accurate to begin with. It was a gift to me from my old Scoutmaster when he retired from working and Scouting in the US and returned to the UK. It still functions perfectly, minus hitting the side of a barn....has never demonstrated the 'jam-o-matic' tendencies that so many of them do...so I basically retired it. I may shoot it from time to time for nostalgia, but its routine shooting days are probably over. Darndest thing though....clean, cold bore was dead nuts. Might have to let Jr. shoot a deer with it just for kicks! I just hope the first shot is true..... [smilie=s:

GhostHawk
12-18-2017, 09:50 PM
What Lube you using?

Try a patch dampened with ATF after your last shot, then let the bore cool.

See what that does to your first cold shot.

I suspect you are having a lube issue.

sghart3578
12-18-2017, 11:44 PM
I had a similar problem with my Marlin 1894C. After a range session I would religiously scrub the bore until it was spotless then oil it. Next time out it would take a shot or two to "walk itself in".

I shoot cast bullets only. Fast loads, medium loads and slow plinkers. All lubed with two or three coats of BLL. Some GC, most PB.

One day after shooting I pushed a dry patch through the bore. It looked really clean. I decided not to scrub it clean with Hoppe's. I just ran a patch with gun oil through it and called it good.

No more flyers.

I now do the same thing with my 336 in 30-30. No more flyers and the bores of both rifles look excellent. It has been a long time since either rifle has seen a bore brush.

Best of luck,


Steve in N CA

SHOOTIST357
12-19-2017, 11:51 AM
bumping up the charge causes my group to go larger. these are just plinking loads and light doses of 4895 been around a long time for plinking.

SHOOTIST357
12-19-2017, 11:59 AM
ATF spends a lot of time on my gun bench -- great lube for revolver internals and shotguns. Never used it in the bore, but I'll give it a shot. No idea what the bullet lube is -- midway bullets with blue lube. I'll try some of my homecast with my lube and see what happens.

SHOOTIST357
12-19-2017, 01:18 PM
Funny things....rifles. I have an old Rem742 in 30-06. The ONLY predictable slug down the bore is the first. When I used to hunt with it, I always prayed I didn't need a follow up shot....cause it could go 8" in ANY direction after the first. :)

I had a bolt action 30-30 that was the same way -- first shot was always 6" high and then the rest of the group was a cloverleaf somewhere else. Worked on that gun a lot of years and never got it right.

SHOOTIST357
01-05-2018, 06:10 PM
So the saga continues... I tried the ATF in the bore. Still the same issues..first shot goes wherever it pleases, then the next 4 are a great group.211151

SHOOTIST357
01-05-2018, 06:11 PM
my home cast with home brew lube211152

SHOOTIST357
01-05-2018, 06:13 PM
By the way -- these are 50 yard groups using a 2-7 redfield. If I could get the flyer fixed I'd be really happy.

FergusonTO35
01-05-2018, 06:55 PM
How old is the rifle? You might be able to get Remlin to put a new barrel on it for you. Once more, I suggest trying at least one more powder that is known to work well in the .30 WCF, like IMR 3031 or Reloder 7. The sweet spot for accuracy with 4895 in .30 WCF in my rifles is 29-30 grains. Have you tried this much powder?

Guns may look identical but each has it's own likes and dislikes. For example, my Glenfield 30 is super accurate with slower powders such as Varget, not what you would expect in this rifle or cartridge. I currently feed it IMR 4064 and get excellent results.

marlinman
01-05-2018, 06:56 PM
Try shooting it dirty. Match shooters always shoot a fouling shot. Any oil/atf etc in the bore will affect the POI.

SHOOTIST357
01-05-2018, 08:14 PM
How old is the rifle? You might be able to get Remlin to put a new barrel on it for you. Once more, I suggest trying at least one more powder that is known to work well in the .30 WCF, like IMR 3031 or Reloder 7. The sweet spot for accuracy with 4895 in .30 WCF in my rifles is 29-30 grains. Have you tried this much powder?

Guns may look identical but each has it's own likes and dislikes. For example, my Glenfield 30 is super accurate with slower powders such as Varget, not what you would expect in this rifle or cartridge. I currently feed it IMR 4064 and get excellent results.

yep-- I have no shortage of powders to try. We run 3031 in my sons 336BL with 170 JFP and it is the most accurate 30-30 I've ever seen.

FergusonTO35
01-05-2018, 10:05 PM
Hmm. Mebbe the bore is a little rough, and the first shot fouls it just enough to settle down. Maybe a box of jword bullets would help it smooth out.

knifemaker
01-05-2018, 10:59 PM
If after shooting are you cleaning and oiling the barrel. if you are, do not do that and see if the next time you go out if your first shot is in the group. I have seen several barrels that will throw the first shot if there is a film of oil in the bore.

WALLNUTT
01-06-2018, 12:33 AM
Put the first bullet in the backstop where it won't bother you and then shoot all you want. If you are going to hunt sight in the first shot and don't worry about the rest. If you don't hit a deer with the first shot you won't stand much of a chance to hit with any.

Texas by God
01-08-2018, 02:22 PM
Try resting just the receiver and buttstock on the bags. When I shoot lever guns I always grip the forend normally and rest my hand on the bags. Try these two things next.
I had a pencil barrel .308 Browning/Sako that the first shot would be 2-3" high from the next ten or whatever. I killed a lot of deer with it but eventually rebarreled it to .250 Savage. Now it will shoot a 2" 5 shot group consisting of 75gr to120gr mixed in the mag- dead center @ 100yds
As trails4u said- funny thing,rifles!
Good luck.

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Texas by God
01-08-2018, 02:24 PM
And I second the dirty barrel motion big time!

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