Author Topic: I need some advise!  (Read 1429 times)

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Offline Sweet 6.5

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I need some advise!
« on: May 11, 2008, 07:08:57 PM »
Hi

Went to the range yesterday to get the my springbuck load ready. I loaded some 120gr
Speers which ave. 2730fps out of my Swede. I used old (about 3 times fired) Lapua brass
and also loaded 6 with new Lapua brass. Same load same length.
I used all the old brass loads to set my scope to shoot 2 inches high at 100 meters. I then moved the target to 200 meters and shot the 6 with the new brass. The speed dropped to 2700 fps with the new brass.

Imagine my surprise when I saw I had a 3 inch 4 shot group, 4 inches high, and 2 about 2 inches below the p.o.a! I never shoot at 200 meters but I am sure I can't stuff it up this much and the same to get 4 together?
Can it be the difference in the loads just because of the new brass or is it that difficult to shoot at 200 meters?
Except for the first 2 shots ( which I think are the 2 away from the others) the rest felt good.

Please help - I have this week to load, ( I don't now what) the weekend to shoot and next weekend is the hunt!

Thanks
Sweet

Offline Brithunter

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Re: I need some advise!
« Reply #1 on: May 11, 2008, 11:47:16 PM »
As your short on time reload using the old brass and test it again. However as time is short do you have another known accurate load? if so make some up and take them to the range and if the 120 grain loads still don't perform use the next load.

Had a similar problem back in 03 just before my hunting trip to America, ran out of bullets and the shop didn't have any more of the same so I had to use another bullet and work up a new load quickly. Same make and weight but this one had a boat tail and you would believe how much difference it made  :o got it sorted now am I am still using the Hornady 139 grain BTSP in my 7x57 even though i prefer flat based bullets I still have a couple of boxes of these BT's to use. Good Luck  ;)

Oh of course you have checked everything is tight?

Offline Grumulkin

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Re: I need some advise!
« Reply #2 on: May 12, 2008, 12:38:13 AM »
Quote
I loaded some 120gr Speers which ave. 2730fps out of my Swede. I used old (about 3 times fired) Lapua brass and also loaded 6 with new Lapua brass. Same load same length.
I used all the old brass loads to set my scope to shoot 2 inches high at 100 meters. I then moved the target to 200 meters and shot the 6 with the new brass. The speed dropped to 2700 fps with the new brass.

A 30 fps difference in velocity probably isn't significant.  It could be caused by barrel heating or fouling or perhaps with a little extra headspace in the new brass.

Quote
Imagine my surprise when I saw I had a 3 inch 4 shot group, 4 inches high, and 2 about 2 inches below the p.o.a! I never shoot at 200 meters but I am sure I can't stuff it up this much and the same to get 4 together?

This is a little confusing.  I take it to mean that 4 shots went into 3 inches at 200 meters.  This isn't bad; it would be equivalent to 4 shots going in to 1.5 inches at 100 meters.  Then you go on to say "4 inches high and 2 about 2 inches below the p.o.a."  I take that to mean that 2 shots were 4 inches higher than the point of aim and 2 were 2 inches below which would give a 6 inch group which is poor.

Quote
Can it be the difference in the loads just because of the new brass or is it that difficult to shoot at 200 meters?

I have noticed differences in accuracy between new and old brass before.  Part of it could be headspace.  It could also be neck tension differences.  It's no more difficult to shoot at 200 meters than at 100 meters provided you have a scope with adequate magnification.  Groups at 200 meters, even with an adequate scope will be about twice the size that would be obtainable at 100 meters.

Quote
Except for the first 2 shots ( which I think are the 2 away from the others) the rest felt good.

Unless you KNOW which 2 shots were away from the others you can draw NO valid conclusions from this.  You also can't make a judgement as to a loads accuracy with a given group unless ALL of the shots "felt good."  It's like the old GIGO saying; garbage in garbage out.

Offline WyoStillhunter

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Re: I need some advise!
« Reply #3 on: May 12, 2008, 02:35:34 PM »
I operate under the assumption that once-fired (in my rifle) brass will have been fire-formed to my rifle and should provide somewhat more consistent groups than loads made up in brand new brass.  I haven't tested this theory...it just makes sense to me (ie. it has face validity).
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Offline beemanbeme

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Re: I need some advise!
« Reply #4 on: May 12, 2008, 03:48:28 PM »
I think a good bit of your problem can be laid to the new brass not fitted to your chamber.  Now that it is fire formed, I'd try it again.  I would, just to be sure, keep it segregated from the old brass for the time being.  And be sure and "hold 'em and squeeze 'em". :D
I disagree that shooting at 200 yards is as easy as shooting at 100 yards assuming that magnification is adequate.  "Stuff" does more than merely double.  And magnification plays little part in it.  As your bullet decelerates, the winds plays on it more, hand tremors, sight picture errors are exaggerated beyond double. Paralax becomes a factor if your bench technique isn't exact.  Shooting a 2" group at 200 yards is much harder than shooting a 1" group at 100 yards. IMO, of course.

Offline Sweet 6.5

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Re: I need some advise!
« Reply #5 on: May 12, 2008, 07:09:43 PM »
Thank you all for the input!!

However as time is short do you have another known accurate load? if so make some up and take them to the range and if the 120 grain loads still don't perform use the next load.
Oh of course you have checked everything is tight?
There is only about 1 inch difference in drop between the 140's stroling along and the 120's. The 140gr Speers have been good to me so I might just take them and then I don't have to worry about sorting out any loads now.
Yes everything is tight - to make me feel better when I saw the 200 meter target,  I moved it back to 100 meters and shot a 1 inch group with some of the 160 I had with me!

And be sure and "hold 'em and squeeze 'em". :D
 

I KNOW !! but with the target all the way out there it messes up the link between my hand and brain!!

Thanks again
Sweet


Offline Brithunter

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Re: I need some advise!
« Reply #6 on: May 12, 2008, 09:28:10 PM »
Hi Sweet 6.5,

       You might be experiencing stability problems, slight ones with the 12o grain bullets. Why I say this is due to what happened to mu buddy with his Ruger 77 6.5x55 back in 2003. His load was a 125 Grainn Nodler Partition at about 3000fps, yep a real stinger of a load whihc shot 1.2MOA groups at 100 yards however at 300 yards it opened up dramatically to over 4". Now we might not think that's bad but this guy shoot High Power and Bench rets at 600 yards and expects 3" groups and under at 600 yards. No matter what he did with that load and rifle he couldn't get it sorted to ended up hunting that season with an old Sako 300 Win Mag and got his deer.

    I lost touch with him due to the move here but recently managed to hook up with him again and asked him about the Ruger. Seems it was the 125 grain partitions, he switched to a Ballistic tip and the problem went away? Now I have shot the 120 grain Spper through my Swedish Mauser and not noticed this but perhaps I have not checked the loads out at 200+ yards. It's probably just the velocity as it slows down it's yawing slightly which if thsi is the case until it stabilises again it will effecet the accuracy. perhaps dropping the powder charge slightly to reduce the velocity?

   That's the thing about ballistics and shooting it's very varible........ interesting but varible.

Offline Coyote Hunter

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Re: I need some advise!
« Reply #7 on: May 14, 2008, 03:09:28 AM »
… There is only about 1 inch difference in drop between the 140's stroling along and the 120's. The 140gr Speers have been good to me so I might just take them and then I don't have to worry about sorting out any loads now.
Yes everything is tight - to make me feel better when I saw the 200 meter target,  I moved it back to 100 meters and shot a 1 inch group with some of the 160 I had with me!


Although I’ve been guilty of the same, trying to develop loads at the last minute is generally not a good plan.

It seems to me you were all over the board with 120’s, 140’s and 160g bullets and, at least in the first post, weren’t sure which bullets landed where at 200 yards.  Since the 140’s have been good to you I’d probably take them and wok with the 120’s after the hunt.

One of the things I do during load development is to shoot each shot over a chrono.  I then record the point of impact and velocity for each shot.  There are a couple of advantages to this.  First, you don’t have to wonder which shots went where when looking at the target later.  Second, it gives a little time for the barrel to cool between shots.  I put the data into a spreadsheet but at a minimum I would keep the targets and the notes that go with them for future reference.

Good luck on the hunt.
Coyote Hunter
NRA, GOA, DAD - and I VOTE!

Offline Sweet 6.5

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Re: I need some advise!
« Reply #8 on: May 18, 2008, 07:36:06 PM »
 ???
Unbelievable - I went to the range Saturday and Sunday, I first moved the target to 150 meters and then
to 200 meters and I made the bull on my target bigger - from an one inch dot to three inches.

The more I practiced the better my rifle shot - the last two groups yesterday both went into 4 inches at
200 meters. One 3 shot group with 140grs and one 5 shot group with the 120grs. I am not going to win any competition
with this but I should be able to get to the important part of the buck. The little buggers must just stand as still as the target!

So Thursday I am off. I am really excited as I have never hunted in this part of our country (Northern Cape - Kalahari Desert ). If all works well I should be able to post a picture of some springbuck next week, while roasting some of the best venison in the world!!

Cheers
Sweet

Offline Brithunter

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Re: I need some advise!
« Reply #9 on: May 18, 2008, 09:36:52 PM »
Yes your correct you won't win many competitions with that accuracy but it's field accuracy. Most places here in the UK check clients accuracy using a 3" circle and you must be capable of putting your shots inside it at 100 yards from field positions maybe using a stick.

Good luck with your hunt and I look forward to you photos  ;D

Offline Sweet 6.5

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Re: I need some advise!
« Reply #10 on: May 25, 2008, 06:28:56 AM »
 :'(

I did not need to worry!! No springbuck !
Just rain, lots and lots of out-of season rain, this is
semi desert and it looked like one BIG mud puddle!
I saw some far away and always on the move.

I nearly settled by going for blesbuck, but decided I really
rather want to hunt springbuck.
 ;D Very good excuse to start planning on the next trip.

Cheers
Sweet