<1moa 270wsm?

Keebler750 said:
Going to the range tomorrow. Hopefully it won't be windy.

I have a big test set up...two bullets, three powders and seating depth tests, plus those factory 130's as a re-benchmark.

Should get SOME kind of useful data out of this. I'll let you all know, of course!!
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Of course that supposes that the R.O will let you go forward and put up targets. This situation may arise if a certain Range hog who has just finished loading 500 rounds for the short guns and has laid in 200 rounds for the Mosin gets there first.;)

See you there tomorrow:D
 
Keebler750 said:
Going to the range tomorrow. Hopefully it won't be windy.

I have a big test set up...two bullets, three powders and seating depth tests, plus those factory 130's as a re-benchmark.

Should get SOME kind of useful data out of this. I'll let you all know, of course!!
Click to expand...


Try loading down instead of up, works every time for me:)
 
Sunday: I found a really weird problem I need help with...tight bolt closure when chambering.

EDIT: I deleted my wierd low temperature fireforming theory....because it was too wierd. :D
 
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How many times have you reloaded the cases? WSM brass doesn't seem to last for too long. I know with my 270WSM the inside diameter of the necks was shrinking as brass migrated up from re-sizing. It measured fine with no bullet in it, but as soon as you seat a bullet it causes the outside diameter to expand. Wasn't able to close the bolt on my rifle after a time. It will actually get so tight that pulling the bullets with an impact puller won't even work.
 
Actually...this is a great learning and thinking exercise but I think I'm barking up the wrong tree with my theory...

A Federal once-fired from my rifle during 60F weather measures .5400" too, and chambers tight. This has been laying around in the box since Sept.

It resized to .5385" and still was tight.

So much for my theory.

How tight should my bolt be? It never seemed like this before. The last time I noticed this feeling it was on my .223 when the primers were sitting proud, so I would notice if my .270 started feeling different....uh, I think....

Now I think I need to recheck and see if something is amiss with the rifle!! Geez this is like a soap opera. Maybe I'm worrying for nothing.
 
Well, I'm back. If you notice, some of the above posts show just how much fiddling around I've been doing and learning this and that.

The weather has been terrible around here to be out load testing, but after the performance of my rifle on the 500M line at Milcun Marksmanship Complex I HAD to do the tests regardless.

It was -15C with a 15 to 20Km/h wind swinging back and forth from over top of my 100M targets. Very cold and nasty but I stuck it out and found some useful loads. I ALMOST got hypothermia doing it.....man I was cold!!!

I didn't even use the chrony. You should be proud, Spencer! LOL!

You all advised that Hodgdon 4831SC would work in the 270WSM. With the 110gr Vmax's I did a step test of 5 shot groups with 64, 65, 66 and 67grains of 4831.

The 64 and 65 gr load was about 1MOA of circular dispersion, even in the wind, and shot to the same POI relative to the bull. The 67 gr load was a perfect row of 1 hole high X 1.5" long...no vertical dispersion (obviously me, or the wind moving the barrel). The 66gr load was about 2MOA circular.

I'm thinking of fine tuning from 63 to 65.5 in .5gr increments. What do you think? I also discovered that I was out from the lands by .050" so I'm going to go 2.735" OAL instead of 2.700". I should find some decent results somewhere in all of this!

I also tried 130 Speer BTSP's and 63 gr of 4831SC gave me 1.5MOA. I was getting really cold and couldn't feel the trigger properly so the rest of that step test just kept opening up and were inconclusive. I stopped before I was done.

At least I'm convinced that load testing will still yield some gains. As I stated earlier I wondered if the barrel was knackered. By the time I'm DONE all this it will be!!

I'm new. Forgive me! :redface:
 
Keebler750 said:
4 times reloaded.

It won't chamber EMPTY resized cases very well either. This is so weird!
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Have you trimmed any of your fired cases to the proper case length yet??? Cases stretch and need to be trimmed.I check my .308 cases after the 2nd or 3rd reload (depending on how hot the load is) and trim when neccessary.

From what I have read I also get the impression that you just want high velocity numbers.

As said earlier, Max loads and high velocity numbers can cause erratic results.Sometimes the best (most accurate loads are in the middle range of the powder load data.

When I work up loads, I work on getting a load that shoots good consistantly.Then I chronograph it and tweak it from there.

My buddy had his Bowning BLR in .270 WSM out at the range today and he was getting about 1.5 MOA on the steel gong at 210 meters with factory ammo (140 & 150 gr. bullets). HE was getting around 3200 to 3300 fps from his 22" barrel.

SKBY.
 
My buddy had his Bowning BLR in .270 WSM out at the range today and he was getting about 1.5 MOA on the steel gong at 210 meters with factory ammo (140 & 150 gr. bullets). HE was getting around 3200 to 3300 fps from his 22" barrel.
SKBY.[/QUOTE]

I just got a new Browning BLR 270 WSM stainless last week, haven't put a scope on it yet but with iron sights factory fed. 130gr. and a barrel that's not broken in yet I was getting under 2" groups at 100yds., needless to say I was impressed :D :sniper:
Dave
 
I just looked this thread.
I'm with Skuulboy on this thought, I would check your brass length if you haven't already trimmed.
When I use a chronograph it is to get uniform veloties as conmsistant as I can , close to the published data that I am using for a specific powder, barrel, etc.
I don't concern myslef too much whether the load is a little slower or faster, as long as the velocity is constant and I don't have pressure problems that are noticible.
This does not always meant that the pressures are within safe operating specsbecause visual pressure signs can be deceiving , but it gives me a better idea of what the load is doing.

Cat
 
In a Rifle mag a gunsmith decribed of building two rifles same calber same action, barrel etc, same everything an the two rifles shot differently. Barrels will react differently to powders an bullet choices, the vibration of barrel will last for a while after shooting a rd, also the barrel swells as the bullet goes down the rifeling. There are soo many variables. George
 
Yup, brass gets trimmed as needed. I keep it on the low end of the .010" tolerance but don't trim every time.

As to neck size and brass flow, my bulleted cartridges have an outside neck of 0.306" and SAAMI limit is 0.314". The only area my brass seems out of whack is at the shoulder to body junction where it's 0.5400" and SAAMI is 0.5381". My resize die will NOT reset this and I don't know why.

As to velocities....yes I'd like a good and fast, hard hitting round that I can count on for hunting that shoots flat and helps me beat the wind at 3, 4, 500yds.

But...

I definately would rather have a sub MOA load that I can predict a high success of going where I aim it for a humane kill. Also, I hate wondering why a particular shot didn't do what I thought it would.

I use a chrony partly as a learning tool (plus I just got it and wanted to check it out), and partly to watch the velocity ceiling, not to get them to be the fastest possible, per se. I also try to read the brass etc.

I am just learning this stuff but I always dig in experiment and immerse myself in the subject. I also value experience which is why I ask you guys stuff.

I went to H1000 because I thought filling the case would bring an accuracy improvement. If it does, it seems offset by the totally different ignition event and it's barrel resonance effects.

Hey, I learned something.

Thanks to you guys, I have had it drilled into my head not to expect much from the MAX end of the scale and just use that as a safety limit.

I am now more into experimenting than ever. I must admit my test methodology was getting lazy and this thread has helped me redo the process.

It's easy to tread water for a while when you're new.

Thanks guys.

I'm using this 'hunting' rifle as my precision ( :eek: ) rig at Milcun and for hunting coyote until I figure out what I'm gonna build.

I am interested in seeing what I can wring out of the 270WSM though..... Sierra has a 135gr Match bullet with a BC of .488 that looks interesting. Hmmmmm.....
 
Question: Does barrel harmonics change with temperature as well? I would expect that it does. Therefore, my loads must chase the temp to keep grouping well? UGH.

Right now I'm trying to get something to work for hunting in the winter. In the summer will that round work as well in this rifle? I know it will have a higher muzzle velocity in the summer. Will that change how the barrel likes that particular load?
 
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