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75gr Sierra seating in .257


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Hi - does anyone reload .25-06 calibre using 75gr bullets (especially Sierra varminter HP's) using 1:10? I have a seating question - basically are they too small/short for .25-06?

 

In detail: I thought I'd have a go with these as a fox round. However having measured the ogive OAL and considered a reasonable 'jump' (my rifle seems to like 0.020") it results in a seating depth of well under a calibre. In fact to get that rule of thumb of a full calibre's depth I'd have a bonkers jump (0.115"). I can get a bit better than a 1.5 inch group at 100yds at a 0.030" jump......but should I, as I suspect, give up, say it's too small and not use them? Is it really meant for say a .257 Roberts?

 

In a way I'm just asking for a final sanity check - 100gr to 117gr will all touch at 100yds with a 0.020" jump OOAL of 2.700".

 

cheers

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There is little to be gained in seating close to the lands in a factory rifle

Take a 55 or 58 grain in a. 243 it will fall out before you get to 20 tho off! Yet to find a factory rifle that would not shoot them great

Same with any calibre just load them a calibre deep in the case.

Getting too close to the lands is actually fairly dangerous as regards potential pressure spikes. Not all bullets in a box are within that 20 tho

Don't get confused bench guns with custom bullets are a very different thing and a quarter moa means a lot more to them at 2-300 yards than it should a guy out to shoot vermin or deer and impress his mates at a 100 yards on paper

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There is little to be gained in seating close to the lands in a factory rifle

Take a 55 or 58 grain in a. 243 it will fall out before you get to 20 tho off! Yet to find a factory rifle that would not shoot them great

Same with any calibre just load them a calibre deep in the case.

Getting too close to the lands is actually fairly dangerous as regards potential pressure spikes. Not all bullets in a box are within that 20 tho

Don't get confused bench guns with custom bullets are a very different thing and a quarter moa means a lot more to them at 2-300 yards than it should a guy out to shoot vermin or deer and impress his mates at a 100 yards on paper

 

this is my point really, so do I try substantially further back or give up......20-40 thou is an accepted rule of thumb I thought so I'm interested in others experiences of much bigger jumps - if these are acceptable?

 

I can shoot far better than 1.5" as can this factory rifle so I regard this group as terrible. God know's what it would be like out on the hill. So what can i do to make it better? If nothing then I'll leave it and just stick to 100gr plus. Shame....it's a bit zippy!

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LW. I would keep to your 100grn bullet choice as it groups well. Look at your pbr on a fox at up to say 1 50yds it would I imagine be point and shoot. If you suspect it's much further out then an inch or 2 higher to compensate for drop would still be in a kill zone.

What are your drops out to say 200yds for example?

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Hi Dougy - how was Diggle? Rob was hurt.......thinks you don't love us no more..........................

 

Roughly speaking 2" depending on weight. Sighted 2" high at 100...gives a potential unthinking range of about 325. I often sit on one of the ridges coming off the hill with my back to a post or tree and the rifle on low sticks. Gives me quite a coverage over the farm and 2 little valleys either side and the flanks of the other ridges beyond.

 

The only reason I looked at the 75's was because I was hopeful for something that might expand a bit better in something smaller.......

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this is my point really, so do I try substantially further back or give up......20-40 thou is an accepted rule of thumb I thought so I'm interested in others experiences of much bigger jumps - if these are acceptable?

 

I can shoot far better than 1.5" as can this factory rifle so I regard this group as terrible. God know's what it would be like out on the hill. So what can i do to make it better? If nothing then I'll leave it and just stick to 100gr plus. Shame....it's a bit zippy!

I can't say it's not other things wrong with the load or your barrel really doesn't like them

 

I can say with a good degree of certainty though that you won't get a full moa improvement with less jump

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Hi Dougy - how was Diggle? Rob was hurt.......thinks you don't love us no more..........................

 

Roughly speaking 2" depending on weight. Sighted 2" high at 100...gives a potential unthinking range of about 325. I often sit on one of the ridges coming off the hill with my back to a post or tree and the rifle on low sticks. Gives me quite a coverage over the farm and 2 little valleys either side and the flanks of the other ridges beyond.

 

The only reason I looked at the 75's was because I was hopeful for something that might expand a bit better in something smaller.......

No such thing as unthinking range out to 325 unless you have a 12 o'clock or 6 o'clock light wind and no contours to speak of

You will also need 1/2 moa from your chosen shooting stance to be sure of a clean shot on a fox and no greater than about 1/2 " trajectory error

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No such thing as unthinking range out to 325 unless you have a 12 o'clock or 6 o'clock light wind and no contours to speak of

You will also need 1/2 moa from your chosen shooting stance to be sure of a clean shot on a fox and no greater than about 1/2 " trajectory error

we were talking drop only.........................(if we talked about EVERY factor we'd just confuse the issue).

improvements in group were the entire point of my post....................so............boiling down what you've said...............you suggest a bigger jump, one in excess of 40 thou?

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we were talking drop only.........................(if we talked about EVERY factor we'd just confuse the issue).

improvements in group were the entire point of my post....................so............boiling down what you've said...............you suggest a bigger jump, one in excess of 40 thou?

I suggest at least a calibre depth of seating and then work on the load

Your gun might not like this bullet but jump being too long is not going to be the issue if we are talking mass produced non vld etc hunting bullets

Factory guns are not cut to accommodate a stated bullet hence the ammo they use must be jump tolerant. This is not a fault in factory rifles it helps keep the user safe from overpressure from jamming the launds

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Jamming the lands won't cause overpressure, what ever that is!

Jamming the lands as you put it should be avoided for other reasons than any excessive pressure concerns.

 

Many a bench rest shooter has enjoyed success with the bullet touching the lands. I said touching, not jamming.

 

I like damson by the way.

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ah no just got it jamming...jam.....damson doh! - damson cheese is good.

 

my parent's damson trees have slowly died.....one sorry specimen remains...might get a couple of pounds off it this year. Keep trying to plant some here but never seem to find anyone with saplings............

Edited by LeadWasp
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LD,

Load up some of your accurate 100grn, ers

stick a target or targets out at 1-2 + 250yds some nice 4inch gongs will suffice, I'm sure you could find some suitable material ;-) shoot em make them clang then sit back,,,,,,, l, smile and tell yourself "that wasn't as hard as I expected"

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Thanks Dougy I'm not stressed about the 100's they shoot very well. They were whopping steel at Catton last time happily at 250 on that 2" high zero.

 

Must have another go at cutting that Hardox - somethings not right with the torch settings.......................

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