Rimfire grouping query

Rimfire bolt action rifles, lever action, pump action and self loading rifles. Air rifles.

Re: Rimfire grouping query

Post by sungazer » 15 May 2018, 10:02 am

Mate the very best of shooters make mistakes all the time. I have seen some of the worlds best shoot on the wrong target, a competition ending score-wise mistake for them. There is so much to concentrate on its nearly impossible not to make a mistake until you have a routine well ingrained and even then things happen that put you off.
I often forget to set my Ocular focus as I have to wind it in to get the bolt in and out which must be done before getting up from the mound. I have to wind it all the way out then a 1/4 turn in. At least its not one that has the lock rings.
sungazer
Sergeant Major
Sergeant Major
 
Posts: 1525
Other

Re: Rimfire grouping query

Post by p3seven » 15 May 2018, 11:02 am

If the rifle is of unhnknowwn provenebce it may have a bent barrel.
Henry 22lr
Savage ll BTVS 22lr
Howa 1500 243 W
User avatar
p3seven
Lance Corporal
Lance Corporal
 
Posts: 154
Queensland

Re: Rimfire grouping query

Post by bladeracer » 15 May 2018, 11:39 am

p3seven wrote:If the rifle is of unknown provenence it may have a bent barrel.


Does a bent barrel effect accuracy though?
Practice Strict Gun Control - Precision Counts!
User avatar
bladeracer
Field Marshal
Field Marshal
 
Posts: 12655
Victoria

Re: Rimfire grouping query

Post by bladeracer » 15 May 2018, 11:50 am

This one shot pretty good.
Attachments
feinwerkbau2 (1).jpg
feinwerkbau2 (1).jpg (22.08 KiB) Viewed 6828 times
Practice Strict Gun Control - Precision Counts!
User avatar
bladeracer
Field Marshal
Field Marshal
 
Posts: 12655
Victoria

Re: Rimfire grouping query

Post by Gwion » 15 May 2018, 1:22 pm

Maybe you need to clean the bolt. Too much grease, oil or crud will interfere with a good strike from the firing pin. Good place to start by giving it a good clean up and then VERY lightly oiling the internals.
User avatar
Gwion
Colonel
Colonel
 
Posts: 3978
-

Re: Rimfire grouping query

Post by Wm.Traynor » 15 May 2018, 2:36 pm

bladeracer wrote:
p3seven wrote:If the rifle is of unknown provenence it may have a bent barrel.


Does a bent barrel effect accuracy though?


A barrel that has been straightened will not group as well as a straight barrel. Got that out of, "Competitive Rifle Shooting", back in the olden days :D
Wm.Traynor
Sergeant Major
Sergeant Major
 
Posts: 1644
Queensland

Re: Rimfire grouping query

Post by bladeracer » 15 May 2018, 2:42 pm

Wm.Traynor wrote:
bladeracer wrote:
p3seven wrote:If the rifle is of unknown provenence it may have a bent barrel.


Does a bent barrel effect accuracy though?


A barrel that has been straightened will not group as well as a straight barrel. Got that out of, "Competitive Rifle Shooting", back in the olden days :D


But does a bent barrel shoot okay if you don't straighten it?
Practice Strict Gun Control - Precision Counts!
User avatar
bladeracer
Field Marshal
Field Marshal
 
Posts: 12655
Victoria

Re: Rimfire grouping query

Post by tom604 » 15 May 2018, 6:42 pm

depends how bent,a 90 degree bend may move the poi a couple of inches :allegedly: :thumbsup:
User avatar
tom604
Warrant Officer C2
Warrant Officer C2
 
Posts: 1053
South Australia

Re: Rimfire grouping query

Post by Wm.Traynor » 15 May 2018, 7:24 pm

bladeracer wrote:
Wm.Traynor wrote:
bladeracer wrote:
p3seven wrote:If the rifle is of unknown provenence it may have a bent barrel.


Does a bent barrel effect accuracy though?


A barrel that has been straightened will not group as well as a straight barrel. Got that out of, "Competitive Rifle Shooting", back in the olden days :D


But does a bent barrel shoot okay if you don't straighten it?


I confess: I have no idea. The author. Jim Sweet, did not go in to that. First things first however. Get it on paper and try it. Not volunteering my rifle ;)
Wm.Traynor
Sergeant Major
Sergeant Major
 
Posts: 1644
Queensland

Re: Rimfire grouping query

Post by bladeracer » 15 May 2018, 9:34 pm

tom604 wrote:depends how bent,a 90 degree bend may move the poi a couple of inches :allegedly: :thumbsup:


Sure, but if you zero it I'm guessing it would still group reasonably well, probably not as well though as the bullets are probably deformed in the curve.

I lean toward the view that a perfectly straight barrel is virtually impossible, particularly in hunter-weight, thus all barrels are bent to some degree anyway.
Practice Strict Gun Control - Precision Counts!
User avatar
bladeracer
Field Marshal
Field Marshal
 
Posts: 12655
Victoria

Re: Rimfire grouping query

Post by marksman » 16 May 2018, 10:53 am

If you ask someone who machines the barrels they bend with the weight of the barrel, in the lathe
hence the forearm bedding to shorten the length of "especially" thin whippy barrels to get them to shoot, look at factory rifles with forend pressure pads
I'm sure that a slight bend wouldn't hurt as a barrel does whip when shot,
but we all know that if the barrel is touching at one side of the forearm it will not shoot well
I think it will be more than one problem in the barrel that would make it not a good barrel
I would not do any testing of a 22 rimfire at 25 yards as you will only see what it is going to be like with the ammo at the distance you will sight it in,
IMO 50-75 yards for a 22 rimfire
some rifles wont shoot very well and you cant make them :allegedly:
“If you do not read the newspapers you are uninformed. If you do read the newspapers you are misinformed”. Mark Twain
User avatar
marksman
Colonel
Colonel
 
Posts: 3660
Victoria

Re: Rimfire grouping query

Post by bladeracer » 16 May 2018, 11:17 am

marksman wrote:some rifles wont shoot very well and you cant make them :allegedly:


I have one of those :-)
My father-in-law's Remington 510. The bore is tightish at both ends for an inch or two, but the whole length of the bore barely touches a .224" jacketed bullet. I put it down to many decades of "fishing" with the muzzle in the water to stun the fish - it's just one long bulge.
The only acceptable accuracy I've managed from the original barrel is by shooting jacketed .224" bullets down it.
Practice Strict Gun Control - Precision Counts!
User avatar
bladeracer
Field Marshal
Field Marshal
 
Posts: 12655
Victoria

Re: Rimfire grouping query

Post by No1_49er » 22 May 2018, 5:28 pm

There's a couple of things to establish in this query.
OP says it is an old CBC bolt action, to which he has fitted a scope. OP also says that a little way down the track he cleaned the bore and it didn't look too pretty.
Starting with the barrel, and not knowing its history, I'd be inclined to keep cleaning, keep cleaning, keep cleaning; even if he wears a bronze brush out doing so until he can push a patch through like it's sliding on glass. Then inspect the bore with a good light to determine how good the rifling is.
Next, look at the barrel crown with a bit of magnification help. Depending on how it's been cleaned in the past there may be some evidence of wear - grooves or dings.
A very thorough clean of the breech area and the bolt with something like brake cleaner to get rid of the last vestiges of old bullet/gun lube.
My favourite lube for actions/bolts after a thorough clean is Birchwood Casey Moly Lube (Dry Film Lubricant). Slippery as the proverbial.
Then there's the matter of the scope.
We don't know what it is, whether it has parallax adjustment, and if not what is the parallax preset to: the web site for the scope may have some info' as to what the parallax has been preset to. The focus could also be an issue adding to the problem.
A previous poster has given a fairly good method to set it up, but should also have mentioned that the reason for pointing at a blank sky (whether that be clear blue or cloudy grey/white) is so that you can not intentionally focus on the object in view. Also, that when making those two turn adjustments he should be looking at anything other than the scope. His eye must relax its focus to "normal". Having made an adjustment he then looks through the scope again. Should be looking to infinity and not AT the cross hair. When the focus is good, the crosshair will immediately appear to be sharp as soon as looking through the scope - no conscious focusing. Once set, it is set for good, for HIS eyes. No need to adjust again.
Only then can he determine whether or not a parallax error will manifest itself. Easily done. Place the rifle on a bench rest (of any sort) so long as the view of a target at the chosen distance can be viewed without touching the rifle. The "target" is then viewed at the same time as moving ones head left and right/ up and down. If the target appears to move then there is a parallax error, which will make his group "loose"! No movement, parallax good AT THAT DISTANCE.

A bit long winded, but hope that helps.
Proud member of "the powerful gun lobby" of Australia :)
No1_49er
Staff Sergeant
Staff Sergeant
 
Posts: 823
Queensland

Next

Back to top
 
Return to Rimfire rifles, and air rifles