Anyone see a problem with this? 3.440 length on 270win

Suther

Suther

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Reloading some 270 win for the first time. SAAMI says max length is 3.340, Mine ended up at 3.440 (brain fart when reading the caliper...)

From what I can gather, at a length of 3.500 the bullet is up against the lands (put a bullet in a case with only a bit of neck tension, and thats how long it comes out after chambering the round) so that would put me around .060 off the lands?

They fit into my magazine.

So this should all be fine right?
 
As long as the bullet is seated deep enough in the case you should be okay o you could just seat the bullet deeper to where you originally wanted it.
 
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From what I've seen on here, most folks that still have enough fingers to type seat the bullet .020 off the lands. So I think you'd be good to go. I'm certainly no expert though. Just musing.
 
If it works in your magazine the OAL is pretty irrelevant.

What is important is the ogive of the bullet in relation to the lands of the rifling

If your jamming the bullet into the rifling, which I doubt, you can increase pressure by not allowing the bullet a small amount of free travel and potentially you can be seating the bullet deeper on chambering a round. If you have peak pressure loads that could be a problem.

You can check this by slowly chambering a round and feeling for unusual resistance.
Sometimes you can see marks from the ogive on the bullet. You can use a marker to paint the bullet to be sure.

If you chamber a round and then extract it and the bullet stays in the chamber that is a sign that you may want to think about seating the bullet deeper
 
kodiakjack said:
From what I've seen on here, most folks that still have enough fingers to type seat the bullet .020 off the lands. So I think you'd be good to go. I'm certainly no expert though. Just musing.
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Yeah, I've certainly seen the .020 off the lands claim many a time, as well as discussions about changing seating depth to attempt to get the ammo more accurate, thats a large part of why I wasn't immediately concerned and didn't seat them deeper yet. I figured I'm better off asking here to be extra sure though.

For the record, there is about .300 of the bullet in the neck. (I'm not sure how much that matters, I've heard you want at least the bullet diameter in the neck, and I've also heard it really doesn't matter)
 
If you are sure you're not jamming the bullet into the rifling at that length, and you're sure it will feed properly from your magazine at that length, and you're sure you have enough neck tension to hold the bullet during handling and shooting, and you think you have a good distance from the lands for accuracy, you're fine. You may be increasing the case volume enough to need some more powder to achieve your expected velocity, maybe, if that matters, but there is no problem with varying from SAAMI numbers in any specific rifle as long as there are no problems created in that rifle from varying SAAMI specs.
 
I guess the only "problem" if you could call it that, is that if you get it zeroed with these rounds, then your next batch at the proper length might be different?
 
kodiakjack said:
I guess the only "problem" if you could call it that, is that if you get it zeroed with these rounds, then your next batch at the proper length might be different?
Click to expand...


The two lengths given are .004" inch apart.
With that little difference in case length, there is NO problem.
 
Suther said:
Reloading some 270 win for the first time. SAAMI says max length is 3.340, Mine ended up at 3.440 (brain fart when reading the caliper...)

From what I can gather, at a length of 3.500 the bullet is up against the lands (put a bullet in a case with only a bit of neck tension, and thats how long it comes out after chambering the round) so that would put me around .060 off the lands?

They fit into my magazine.

So this should all be fine right?
Click to expand...

H4831 said:
The two lengths given are .004" inch apart.
With that little difference in case length, there is NO problem.
Click to expand...

It's actually .100, not .004.

Still, I don't know that a tenth of an inch would make a difference?
 
kodiakjack said:
I guess the only "problem" if you could call it that, is that if you get it zeroed with these rounds, then your next batch at the proper length might be different?
Click to expand...

If they feed well from the magazine and shoot good, i just might keep them this length. Lol

This is literally my first batch of 270 reloads, so I'm sure there will be many variations on powder charge and seating depth before I settle on a load for the gun.

Currently I have 10 of each 52gr and 53gr IMR4350. The original plan was to make up 10 each at 54 and 55gr too, but I haven't gotten around to it, and if I do them today before my range trip it'll cut into my range time so we'll see...
 
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Went to the range yesterday, and the results are very promising.

With factory ammo, the best groups I could shoot with this rifle were over an inch, most around 1.5". I have changed stocks (factory black to factory camo stock) and bedded the new stock, in addition to the hand loads.

The groups were shooting high and to the right, so most of my 52gr loads weren't on paper, but I got three 3-shot groups of the 53gr on paper.



The group in the middle of the page was shot before adjusting my scope, the two bottom ones were shot after. The bottom left one obviously isn't very good, I didn't even measure it. I was shooting right beside a guy going to town with a revolver and I can be a bit flinchy. The other two groups measured under 0.6" though! I am very satisfied with my results so far!
 
This thread is all fouled up, because in the first post the OP admits to reading his digital instrument wrong, and no one pays any attention to what he said!
He measured it as .004" of an inch difference. Even this is crude measuring, as any difference is virtually negligible and can be ignored.
 
H4831 said:
This thread is all fouled up, because in the first post the OP admits to reading his digital instrument wrong, and no one pays any attention to what he said!
He measured it as .004" of an inch difference. Even this is crude measuring, as any difference is virtually negligible and can be ignored.
Click to expand...

I was off by .100 actually. Meant to make em 3.340, made em .3.440 long.

And my caliper isn't digital...
 
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