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Saguaro Firearms
November 2, 2009, 11:33 AM
ok i have a question, yesterday im at the range to zero for a hunt, and i noticed my cold bore shot is a good 3 inches away from the rest of the group at only 100 yards, the second, third, forth, and fifth are all right on top of each other, i let the rifle cool and repeated the process 4 times, only to get the same result each time. my question is should i adjust the scope for the cold bore shot? or halfway in between the cold bore shot and the rest of the group?
this is gonna be my first hunt btw.

Wild Bill Bucks
November 2, 2009, 12:12 PM
Almost every rifle I own doesn't like a clean barrel. I always shoot a couple of primers off, with no load in the barrel, before loading. This fouls the barrel so that my first shot is as accurate as any other. If you are going to clean out between every shot, and the first shot is consistently in the same spot, then you can sight in with that shot. In the field it is difficult to always clean between shots if you need to get re-loaded quickly, so I would foul the barrel and then sight in with the rifle that way. This procedure is for muzzle-loaders.
If you are sighting in a high powered rifle, then simply sight to the group, and don't clean your rifle before the season is over.

Saguaro Firearms
November 2, 2009, 12:19 PM
i think it has more to do with temperature, i have not cleaned the bore any time during the working up of the load or trying to zero.
its a savage 270 btw

davlandrum
November 2, 2009, 12:26 PM
To answer your question - hunting requires 1 shot from a cold barrel that hits exactly where you expect it to.

a 3" variation at 100 yds after just 1 shot is way out of whack. I am sure some of the really smart guys can give you some possible causes.

Wild Bill Bucks
November 2, 2009, 12:29 PM
If the rifle is that cold sensitive, I would adjust the scope in between the cold bore shot and the warm barrel group. I suspect that, as you are working up loads, that you will find a 1/4 grain increment, one way or the other, may solve the problem for you. If you are working up loads you might find another brand or type of bullet that will solve the problem also.
As far as most 270's go, they will all become pretty hot after the third shot, so unless you intend to hunt with multiple quick fired rounds when you hunt, I would sight in with the cold bore shot, since it will be the one you are hunting with.

Saguaro Firearms
November 2, 2009, 12:31 PM
i think i will just zero on the cold bore shot, the first shot is gonna be the important one, if i need another at least i have a general idea of where its gonna go,

Saguaro Firearms
November 2, 2009, 12:33 PM
and your right davlandrum, 3 inches is way out of whack, half inch i could deal with,

Art Eatman
November 2, 2009, 12:36 PM
Yeah, I'd zero for the cold-bore shot.

My father had a sporterized Springfield that always put the first shot 2" high. He rebedded it. No change. He rebarrelled it. No change. Go figure. After that first shot, you could shoot all day into a common group.

Stubborn cuss that he was, he just allowed for the 2", and killed a bunch of deer with that rifle. He even shot a turkey in the neck and commented that he sure hoped the rifle stayed with the program, since he had to hold for the breast. :)

bigjack59
November 2, 2009, 12:37 PM
Something else is up, you guys are right. No way three inches at 100 yards is right for cold to warm grouping.How many rounds have you put through this rifle?

Christchild
November 2, 2009, 12:51 PM
Before making any adjustments, I'd get the bore as clean as possible, then fire 1 Cold Bore Shot at 100 yds.

Whether or not it was still 3" high, let the Bore completely cool, and without cleaning, fire 1 more Cold Bore Shot.

I'd want to see if there is any change in that 1st shot, with a clean bore VS. 1 fouling shot through.

You already know that You'll get a 3" high hit with a cold, fouled barrel. Try that 1st one when it's clean. Then, if You get the same result, I'd do what the above Posts suggest. Adjust to Split the Difference.

If You get a good shot (or 2 or 3) after it's clean, then clean and prepare everything else for Your hunt.

Rifles can be very "funny" (for lack of a better term). I have a .270 Win. with a Custom Barrel, and it does not like 130 grain bullets. 90 grain, 110 grain and 150 grain bullets... That rifle shoots all of them like a Champ. But out of all of the 130's I have, Barnes XFB, Sierra MatchKing (135) and Hornady Interbond, those all shoot the same, no matter what I do. Through ALL of my development trials, they've all been consistent at 1 1/4" to 1 1/2". All 130's.

But my first reaction to Your dilemma, would be to get the bore clean first, go through a little more process, before I adjusted. Then, if everything stayed the same as it is now, go ahead and adjust.

kjack
November 2, 2009, 01:46 PM
Waiting for a barrel to cool between shots (action open, letting air circulate through the barrel) is supposed to take a while. I have no idea of the exact time, but you might have to wait 1/2 hour messing with other stuff while you wait for your barrel to cool to room temperature.

One gun hack wrote that he kept a special target for his cold shot. Every time he went to the range with that rifle, he would put up the cold shot target to get a trend before he did his usual fiddling with loads. (This assumes you use the same ammo at the same range for the cold shot each time and no scope adjustments.)

The point he made about shooting for consistency (groups) was that he didn't need to actually hit the bull to measure a group with a different powder set-up and could go about load testing with no other changes to the rifle and scope.

I don't know if the once-in-a-while hunter (like me) could even find the cold shot target for each outing, but it's a reasonable idea.

UniversalFrost
November 2, 2009, 02:48 PM
Saguaro Firearms

you wouldn't happen to be under the name of one of the gunshops here in Sierra Vista?

if so, I welcome aboard and make sure to PM me and i can shoot you links to more AZ specific gun boards.

also, you bedded and inletted the stock yet? you tried different scopes? you tried loctite on the base screws? you made sure you just are not flinching (serious, have someone else shoot the gun and see where it shoots compared to you).

also, like wild bill mentioned a dirty bore will shoot the same cold or warm (normally). when I sight in a deer rifle and I have a good zero I will clean it really well and then fire a few (3 or so) shots thru it to reverify zero then leave it uncleaned and take it deer hunting in that condition.

if you are in Sierra Vista, we could meet up at the range some time or if you want to shoot with a bunch of us that are local we have shoots on BLM land about once and month and many of us bring our full auto and other NFA toys and there have been several belt feds that show up. also plenty of room for 50's and .338 lapuas if you want to shoot past 1000 meters.

PM me if interested.

JOE

Saguaro Firearms
November 3, 2009, 12:11 PM
bigjack59 to answer your question about round count. factory loads id say 400 rounds, hand loads another 300 or so. i have not shot a string of more than 5. although some of the hand loads have been on the warm side but nothing too crazy.

Saguaro Firearms
November 3, 2009, 12:19 PM
UniversalFrost Yes... that is my shop. small world huh? i havent tried tinkering with the screws, i have switched scopes. but not during the working of this load. and as far as flinching goes, i can usually call out a flier before it gets out there. but one thing is this rifle had a very ugly trigger on it, its heavy.. probably in the 5.5-6.5 pound range. that could have something to do with it. but ive shot more sub moa groups with this gun than my 40x. all the rounds i have through it have pretty much been on paper, so i always had a fouling round. im not gonna get a chance to get that fouling round here. but i guess a good cleaning probably couldn't hurt. my hunt is on nov 13th and i dont have the time to get more bullets in and rework the load. im using barnes tripple shock and im pretty sure thats most of it. i have not in my lifetime gotten those to shoot in any of my guns, but im gonna be hunting a fairly large animal and a rather close distance, no i can give up a little bit of accuracy for good bullet performance.

UniversalFrost
November 5, 2009, 10:18 AM
replied to you pm with more questions for you to answer. but with the hunt so close looks like adjusting scope to the cold bore shot is the best bet.

have fun and if it is the same buffalo hunt my neighbor did last year (and I was supposed to go on this year:mad: ) you will have fun.

when you get back PM me and we can take a look at your gun and get the problem fixed ( i my wife is due with our 2nd kid in november, then have december and january deer seasons, but can find some time to look at it during that time frame if I bag my deer early, or can look at it when the seasons are over).

bejay
November 6, 2009, 07:46 PM
my savage 270 does the same thing the first shot on a cold barrel is always about 3 inches low from the rest of the group. I just adjusted to split the difference while it might be more of an issue at longer ranges its not really a problem for most my shots wich is usually under 100 yards.

Saguaro Firearms
November 6, 2009, 09:58 PM
wow! congrats!! well i know short on time to start playing with the scope, sad thing is i just ordered a barrel, gonna turn it into a 338-06, got the barrel dies, bras, bullets coming, hope i can get it all settled in in a week. im very exited its gonna be my first big game hunt. ill be sure to post a pic or two, i also plan on video too.

Saguaro Firearms
November 6, 2009, 09:59 PM
bejay, i never noticed if the rifle always did that. i have never actually paid attention to the cold bore shot, this will be the first time ive ever actually hunted with it. but we shall see, after the re barrel that is

jrothWA
November 6, 2009, 10:33 PM
slide it down the barrel and check the clearance between the stock & barrel.
You mght have a contact point affecting the group.

Action screw must be tight.

Saguaro Firearms
November 6, 2009, 10:38 PM
the stock has been relieved already.. thanks though

James R. Burke
November 10, 2009, 07:25 PM
My rifle for hunting deer I start with a clean barrel. If it checks out o.k. with about 15 shots or less I just leave that way till the end of season. Just wipe it down with oil after each use. At the end of the season I go thru the bore, and everything real good. If I go out, and end up shooting a bunch I will clean the bore good, and go back out and take a few fouling shots then again leave that way to the end of season.

DWARREN123
November 10, 2009, 11:26 PM
I would first check that stock to action fit is correct, check for stock to barrel fit, then fire it again. If the same results I would adjust the sights/scope for the cold bore because that is the main shot you will use in hunting.

Saguaro Firearms
November 11, 2009, 02:36 AM
thanks for all the help guys... i re barreled the rifle today in 338-06
also loaded 5 batches of 5 all different powder weights. im gonna take it out tomorrow morning and see what she will do. if it doesn't work out ill just take the 7. shes ready to go and prints beautifully.

Saguaro Firearms
November 11, 2009, 09:22 PM
the re barrel worked beautifully, half inch all day and even the fire forming were under an inch

FrankenMauser
November 12, 2009, 02:14 PM
My Ruger .270 is similar.

At about 60 degrees Fahrenheit, A cold bore shot is about 2" high and 1" right, while the others drop right into my intended POI. If I let the barrel cool back to ambient temp for each shot, it's a beautiful cold bore group, so I know it's consistent.

However, temperature variations actually shift my POI. Warmer temperatures push my POI up, and slightly left. Colder temperatures push my POI down, and slightly right.
Temps below freezing cause some really erratic performance. Whether it's the laminated stock, or the metal itself, something is temperature sensitive.

I think it may be a pressure point in the fore end. I just haven't felt like messing with it, since the performance is predictable.

Saguaro Firearms
November 12, 2009, 04:29 PM
sounds like a strong possibility to me... but yeah if you know what its gonna do and your comfortable with it. i wouldn't mess with it either.

Daryl
November 12, 2009, 06:04 PM
Universal Frost,

Any connection with Frost Taxidermy in SV?

Daryl

Colorado Redneck
November 13, 2009, 10:50 PM
I had a Remington 270 semi auto once. Darned thing would just not stay consistent. My son (who is an excellent shooter) and I took it to the range after a couple of really screwy hunting episodes, and shot it about 20 times to get it where we wanted. That was 2 inches high at 100 yards. We got a 1.6 inch group of 3, which aint great but will do for a deer rifle. We let it cool a few minutes between each shot.

2 days later we went back to the range. The first shot I made was 6 inches high and at least that far to the left. Then my son shot it and was nearly at the same place.

For some reason, that gun woul not hold zero. I traded it for a Winchester model 70 and mounted the same scope with the same rings on that gun. It worked fine.

The effort required to find the problem was more than I was interested in putting out. A different gun that I liked would have been different.

UniversalFrost
November 14, 2009, 01:55 AM
Daryl,

No i have no connections and didn't even know about them. Hope they don't infringe on my copyright and trademark rights :D

I use braggin rights taxidermy in whetstone for my trophies.

http://www.bragginrightstaxidermy.com/default.html