I'm confused by my 7x57r reloads, please advise!

njc110381

Well-Known Member
Right chaps. I've always thought myself to be a fairly competant reloader but I've come across something that's really got me beat! So I'm looking for some pointers!

My combi gun isn't grouping too well. Never really has and this has been confirmed by the fitting of the scope. I can't get inside 4" at 100 yards with the factory ammo I have and I think I've just sussed out why! I've always loaded about 20 thou from the lands, maybe more with Barnes TSX. Well as an experiment I thought I'd draw a pencil line around the bullet against the case and give it a few taps with the kinetic hammer to pull them out a bit, then stick them in the rifle and close it to get the approximate max OAL for that bullet type by seating them with the throat of the rifling. All seems simple you may say? What's the problem? Well...

Factory ammo is 2.855 OAL. I've hammered them out to 3.122 and pencilled a second ring on the bullet. They still close with no resistance. I tapped it a little more and out it fell, so less than a bullet width was inside the case at last known measurement! Arse! What should I do next? :unsure:
 
Could it be that the rifle was originally chambered for a bullet with a more defined ogive than what you are using? Maybe a roundnose instead of a spirepoint - that might allow the bullet to engage with the lead of the rifling at a point further back and thereby retain more of the base in the neck of the cartridge.
 
Orion,
I have a Sauer & Sohn drilling in this calibre and have had no problems with accuracy.
I agree with njc that if it is an older gun the chambering may have been set up for heavy for diameter bullet with too much freebbore for spitzer which is really a bolt action head form IMHO.
Have you a got long roundnose bullet to try? or if not use a bit of 7mm brass rod (if you can find it, spin the front up in a drill chuck to approximate a bullet front shape then pop it in a case and try out where it lies for OAL. Quick and dirty.
I use RWS teilmantelrundkopf (theres a mouthfull) with excellent results.
RWS doppelkern are not so loved here in the fatherland due to using them on roe the hematome damage caused.
Martin
 
Orion,
I have a Sauer & Sohn drilling in this calibre and have had no problems with accuracy.
I agree with njc that if it is an older gun the chambering may have been set up for heavy for diameter bullet with too much freebbore for spitzer which is really a bolt action head form IMHO.
Have you a got long roundnose bullet to try? or if not use a bit of 7mm brass rod (if you can find it, spin the front up in a drill chuck to approximate a bullet front shape then pop it in a case and try out where it lies for OAL. Quick and dirty.
I use RWS teilmantelrundkopf (theres a mouthfull) with excellent results.
RWS doppelkern are not so loved here in the fatherland due to using them on roe the hematome damage caused.
Martin

:confused: I thought that was what I was suggesting the cause might be! Did it not come across too well? :D
 
That would be the answer if I wasn't using a blunt nosed bullet already! Having said that it's a light one - 140grn, so perhaps a 175 would be better? I'm thinking of buying a box of heavies to try!
 
I have been having same issues with my 7x65r. Actually had a chat with peter hambrusch who built mine. Because the bottom barrel is soldered to the top, the barrel as it warms up warps upwards. When shooting groups let the barrel for a good few minutes between shots.

As has been said above try different bullets. I tried 160gn speers. Not brilliantvwith any load. Went to 139 gn hornadys and all went onto two inches and have one with 51.5gn oh imr 4831 thart holds an inch quite easily.
 
In the older combi-guns - drillings - I suspect that the chambers were reamed out for the old-fashioned cartridges which were loaded with longer, round nosed bullets. Thus a much longer leed or freebore was used before reaching the rifling.
Despite arguments to the contrary by those who like their bullets to engage the rifling, the freebore was decided upon in chambers by gunsmiths so that the bullet could have a smidgin of free travel before hitting the rifling - thus preventing chances of excessive pressure.
The argument becomes academic if you end up deficient of an eye or other part of your anatomy.

The mystery deepens and it might just work around how old the rifle is and what rifling twist was used. Perhaps your barrel does not like the lighter-faster bullets and will not stabilise them.
It might prefer a real heavyweight roundnose bullet thundering along at a more sedate pace, a real grass and brush divider.

In the worst scenario - if the rifle is an older model and once used cartridges with corrosive primers, your rifling just forward of the chamber might be worn, or at the muzzle.
Some of those sweet old rifles just got worn out.

There is - in some calibres - a very real division in what bullet weights some rifle twists will stabilise properly, but, for instance, the 6.5mm seems to be pretty tolerant with a 1 in 9 twist stabilising anything from 87 grains right up through to 140 - and more, BUT, in modern terms of required velocity, a 6.5mm. can sometimes be a bit difficult to get up to speed and generaly works around a more moderate velocity.

YES - you avid 6.5mm users, I know that the 6.6 Swede can obtain pace with certain powders, particularly from the Hodgdens range.
My 6.5mm used the German cartridge with the 57mm case, and that proved to be a bit stubborn as regards reaching over 2800 fps.

I'd be tempted - unless some kind soul has already provided the solution for you, to consult with a reliable riflemaker. I wish you all success.
 
Right chaps. I've always thought myself to be a fairly competant reloader but I've come across something that's really got me beat! So I'm looking for some pointers!

My combi gun isn't grouping too well. Never really has and this has been confirmed by the fitting of the scope. I can't get inside 4" at 100 yards with the factory ammo I have and I think I've just sussed out why! I've always loaded about 20 thou from the lands, maybe more with Barnes TSX. Well as an experiment I thought I'd draw a pencil line around the bullet against the case and give it a few taps with the kinetic hammer to pull them out a bit, then stick them in the rifle and close it to get the approximate max OAL for that bullet type by seating them with the throat of the rifling. All seems simple you may say? What's the problem? Well...

Factory ammo is 2.855 OAL. I've hammered them out to 3.122 and pencilled a second ring on the bullet. They still close with no resistance. I tapped it a little more and out it fell, so less than a bullet width was inside the case at last known measurement! Arse! What should I do next? :unsure:

Crimp your loads or go to a different bullet.~Muir
 
I don't know why I didn't think of crimping. Thanks Muir!

As the rest of you are saying, it may be that the rifle is designed to use really long bullets? I will up the weight a little and see what that does, as well as crimp some of the loads I have now. I'm not sure that I should just run a crimper over the loads without reducing them though so perhaps I should just pull a few of the ones I have and start again with the cases? Supposedly all the usual pressure signs just don't happen in low pressure rounds and it's said that the gun will more likely blow up before you get a sticky extraction etc?
 
Muir, please can you give us novices a muir guide to crimping. I have set my hornady die to give a bit of tension on the neck, ie screwd down till it just meets the neck and the another quarter turn. I am using the horandy 139 gn softpoint spitzer seat to canelure, but I can't see much of a crimp - not like a factory crimp.

Many thanks
 
You won't see much with most die sets. In fact you need to check your set-up instructions as to whether or not yoiu have the capacity to crimp for your individual die set. You have it down though: that is how I would do it. Lee will make a factory crimp die for any caliber if you provide dummy rounds for them to work on. An "emergency" crimp for most bottle neck die sets can be had by removing the expander / decapper from some die sets and running the loaded round gently into the FL sizer, just until you feel resistance. This will form a shortr "taper crimp" on the case mouth. Just don't get carried away with this method!

Unless I am doing something extreme in the way of crimping, over hot loads, I generally don't worry about crimp causing pressure problems. All it does is to make the pressure needed to release the neck from the bullet ("pull weight" in proper terms) uniform.~Muir
 
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