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7x64 problems
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A friend of mine has just bought a browning 7x64 with a 20" barrell. He is using 175gn speer nitrex but it wont group under 4" @ 100yds
has any body any input which might throw light on what the problem is.
he has fitted new scopes s&b 6x42
bedding screws tight and the barrell is free floated>
Many thanks
Griff
 
Posts: 1179 | Location: scotland | Registered: 28 February 2001Reply With Quote
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Two questions: #1-how tight are the scope ring screws

and

#2-how many different loads has he tried in the gun?

 
Posts: 1723 | Location: wyo | Registered: 03 March 2001Reply With Quote
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Hi Curtis,
the scope rings will no doubt be on tight I think he tightens them up with a torque wrench!!
unfortunately he only has access to these bullets I mentioned earlier.
perhaps a lighter load might give better groups.
dont know what the twist is in this rifle so dont know what bullet to advise him to use
He shoots wild boar so needs a fairly substantial round.
p.s. the rifle is new.
griff
 
Posts: 1179 | Location: scotland | Registered: 28 February 2001Reply With Quote
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ok, i'll give you handloads for 175grainers in the .280 rem (7x64mm American). Tell me how it goes:
POWDER
IMR3031 37.1gr (2200fps) 39.4 (2300fps)
41.6 (2400fps) 43.8 (2500fps)
IMR4064 38.1 (2200fps) 40.4 (2300fps)
42.6 (2400fps) 44.9 (2500fps)
H4895 38.9 (2200fps) 41.1 (2300fps)
43.3 (2400fps) 45.5 (2500fps)
IMR4320 38.5 (2200fps) 40.9 (2300fps)
43.3 (2400fps) 45.7 (2500fps) 48.1 (2600fps)
H380 40.2 (2200fps) 42.4 (2300fps)
44.6 (2400fps) 46.8 (2500fps)
IMR4350 46.4 (2300fps) 48.3 (2400fps)
50.2 (2500fps) 52.1 (2600fps) 54.0 (2700fps)
WIN760 43.6 (2200fps) 45.8 (2300fps)
48.0 (2400fps) 50.3 (2500fps) 52.1 (2600fps) 54.0 (2700fps)
H4831 49.0 (2300fps) 50.9 (2400fps)
52.7 (2500fps) 54.6 (2600fps) 56.4 (2700fps)
H450 48.9 (2300fps) 51.0 (2400fps)
53.0 (2500fps) 55.0 (2600fps) 57.0 (2700fps)

now you say he only has access to 175grs or he can only get 175grs cheaply?

 
Posts: 1723 | Location: wyo | Registered: 03 March 2001Reply With Quote
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Measure the twist, the 175 gr is happy with about a 8 to 9 inch. Could have a horrible crown. Where is the bullet in relation to the lands? Is this a new rifle? Or a used one? Might need a good barrel cleaning with a copper remover. Sounds like a Mannlicher stock with such a short barrel, but you said it is floated. I would slug the bore to determine the bore diameter, there is a good variation among 7mm barrels. Try using a different scope. What is the barrel contour, might be a skinny whip? Which Browning action? What type scope rings & bases? Might need a lighter bullet.
 
Posts: 1055 | Location: Real Sasquatch Country!!! I Seen 'Em! | Registered: 16 January 2001Reply With Quote
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John Ricks likely has it in that the CIP twist for a 7x64 is slower than a 7x57. I can't exactly remember the figure but 1in10 rings a bell. The standard max bullet weight for 7x64 is around the 160gr area. If it is indeed slower than 1in9 it might stabilise a 175gr RN but allmost definately not a 175gr spitzer (as the speer Nitrex is)

From experience getting continental ammunition is a nightmare in the UK. The importers are absolutely the most useless outfits I've ever come across.

Anyhow try RWS and Norma (Dynamit Nobel)who may give you a local stockist who may have or get some stuff Tel 01579 362319 Also try SAKO (GMK) tel 01489 579999 ask for Stephen Day

Can't swear that SAKO actualy do 7x64 but it's worth a try.

A Norma 156gr Oryx load would be good for Boar in your friends rifle (bonded bullet), Norma plan a 156gr Oryx load in 2001 (part no 17053) and the bullet itself also in 2001 (part no 67004)

[This message has been edited by 1894 (edited 08-10-2001).]

 
Posts: 2258 | Location: Bristol, England | Registered: 24 April 2001Reply With Quote
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thanks for the replies,this is a new rifle with new smidt and bender scopes, so one could presume that they are not at fault.sounds to me as if the twist as you mentioned earlier will not stabilize the heavier bullets. one of the problems is that this friend of mine works on a private estate in france and the estate armourer only has the 175gn.My main interest in this is that I have had an invite to shoot wild boar with this rifle, and I dont fancy shooting at something that if you dont kill it it could kill you!!! not sure how my 2506 would perform?
I shall pass on the info and hopefully he will be able to use it.
Many thanks
Griff
 
Posts: 1179 | Location: scotland | Registered: 28 February 2001Reply With Quote
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I hope I'm not over stepping my bounds by making the suggestion that perhaps (if this is possible) you send your friend a box of 150 grs to try. He might be better served using them then the 175s.
 
Posts: 1723 | Location: wyo | Registered: 03 March 2001Reply With Quote
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Hi Curtis
Great suggestion but unfortunately sending live ammo through the post is a definite no!no!.
UK laws are far stricter than yours, we cant even buy or send bullet heads without showing your firearms certificate.
have suggested to him tonight that he buy some reloading gear and start having some fun!
thanks
Griff
 
Posts: 1179 | Location: scotland | Registered: 28 February 2001Reply With Quote
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Put a shim under the forend of the barrel, then try 2 shims...Many rifles shoot better if the barrels are stabalized out front...

Free floating isn't the cure all of all cure alls...It works sometimes and sometimes it doesn't...depends on barrel viberations. The shims will dampen this viberation...Bet it works for you.

------------------
Ray Atkinson

ray@atkinsonhunting.com
atkinsonhunting.com

 
Posts: 42203 | Location: Twin Falls, Idaho | Registered: 04 June 2000Reply With Quote
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Dont trust a scope on brand alone: I had trouble with a Zeiss 6x42. For checking I would replace that scope with one You really trust. Then check that all screws are really tight.

Good Shooting! H

------------------

 
Posts: 828 | Location: Europe | Registered: 13 June 2001Reply With Quote
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thanks for all the replies. have passed on the message, and with that he went out and bought some rws 120gn cone point!.
1.5"@200yds.
one happy shooter
thanks once again,
Griff
 
Posts: 1179 | Location: scotland | Registered: 28 February 2001Reply With Quote
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