Range report with first reloads

[CptnAwesome]

Finally got to try out my first batch of reloads in my mossberg patriot.
270win, 130 gr Sierra gameking Spitzer over H4831sc. Started at 56gr and worked up top 59.5 max. Worst group was about 2" at 100yds with best group of the day (1") coming at max recommended 59.5gr.
Overall length was only 3.24" and I haven't found out what length I'll need to get to the lands, and don't really want to seat to lands, but max recommended length is 3.34". So I'll work it to there.

Any thoughts or recommendations?

 

[readyeddy]

Nice groups. I would also increase OAL.

 

[Andrew Leigh]

Nice groups. I would also increase OAL.

What would your reasoning be for increasing the COL?

 

[41 Mag]

What would your reasoning be for increasing the COL?

It will change the jump the bullet makes to the lands. Sometimes this will change the harmonics of the load and can help to shrink groups.

When I am working on loads for hunting, most of, if not all of my rifles feed from the magazine which is the max OAL I can load to. I will usually work up to a predetermined velocity range that I choose to work within. While I am working up I will be looking for accuracy as well with each load increment.

If I see something promising, I will then seat the bullets in using as close as I can get to .005" increments. Sometimes things that look great to start with head south, sometimes they get tighter. I might work back to the listed OAL for the round being loaded, and sometimes I don't have too. If I am still getting within a hundred or so FPS of the velocity range I want to be in, and am getting 1" or so accuracy, for hunting that is plenty for me. I would MUCH rather have something consistently grouping at or under 1" and be a little shy of say 2850fps than have something that shoots 2850 and only groups 3' at best.

Yes you can have both the top end velocity and great groups and I have a couple of rifles I DO load like that, but for the most part those are for specific uses at longer ranges, where the others will be used at or under 200yds the majority of the time.

 

[spitballer]

Nice shooting! I've never used anything larger than a .223 since leaving the army so I really can't speak from experience regarding a .270. But when I first saw the group on the left with the two shots high and left it immediately reminded me of some of my experimental groups, and the struggles I've had stabilizing bullets that are being twisted just a fraction too fast.

Not too long ago Bart B posted that [top shooters twist the bullet just fast enough to stabilize it, and no faster], and over time I'm beginning to understand a little more about this. I'm convinced that over-twisting is not such a big deal as long as there are no irregularities in the rifling. In my case, I didn't get the super-duper honing with this latest barrel (12" twist) and as the tooling marks have smoothed out it has been harder and harder to stabilize the 55 grain BT bullets I'm using.

My sense is that if a bullet is twisted just fast enough to stabilize it, it wants to correct itself, whereas a bullet that is even slightly over-twisted wants to get worse. Maybe other members can shed more light on this subject.

I'm not suggesting that this is what occurred in your target on the left, by any means. There are a zillion reasons why flyers occur and in my case, at least, most of them are still a result of my inability to stay steady at the bench. But my next experiments will be conducted with 64 grain Bergers, which are probably more closely matched to the rate of twist. Thanks for the interesting post.

 

[CptnAwesome]

Made my own little tool to find the length to seat to lands in my rifle. Max recommended OAL is 3.34. I hit lands at 3.2715. I've retested it 4 times with same outcome

(1) I assumed that since max recommended was 3.34 that most factory 270's could accommodate that length without being jammed into the lands, I guess I was wrong,,, but then again I'm very new to this.

(2) Correct me if I'm wrong but .01 is fairly safe distance to stay off lands without fear of getting into pressure spikes.

 

[W.E.G.]

.01 is fairly safe distance to stay off lands without fear of getting into pressure spikes.

That should be fine with lead-core bullets.

If this is a magazine-fed rifle, intended for hunting/utility work, you are probably better off to load to magazine length, and play with powder charges to get the best accuracy available at magazine length. You won't want to keep some "long rounds" in your field kit because you find that they shot a half-minute tighter on that day at the range. Just not worth the hassle to keep all the odd bits sorted.

Find an accurate-enough load, and practice with your rifle.

 

[CptnAwesome]

Thanx for the feedback guys, it's priceless!

 

[Andrew Leigh]

It will change the jump the bullet makes to the lands. Sometimes this will change the harmonics of the load and can help to shrink groups.

In my experience the "harmonics" are determined by the barrel length and the jump cannot alter this.

I do agree that altering the jump can shrink groups but for a different reason; simply because you are altering the internal pressure and or the inertia of the bullet to overcome the lands. This alters the bullets speed and the corresponding barrel time.

When I am working on loads for hunting, most of, if not all of my rifles feed from the magazine which is the max OAL I can load to. I will usually work up to a predetermined velocity range that I choose to work within. While I am working up I will be looking for accuracy as well with each load increment.

If I see something promising, I will then seat the bullets in using as close as I can get to .005" increments. Sometimes things that look great to start with head south, sometimes they get tighter. I might work back to the listed OAL for the round being loaded, and sometimes I don't have too. If I am still getting within a hundred or so FPS of the velocity range I want to be in, and am getting 1" or so accuracy, for hunting that is plenty for me. I would MUCH rather have something consistently grouping at or under 1" and be a little shy of say 2850fps than have something that shoots 2850 and only groups 3' at best.

The reason why the results sometimes get better and or can get worse is that in changing the internal pressure you may be moving away from or towards an accuracy node. So getting closer to the lands does not always tighten the group as you have experienced.

 

[Andrew Leigh]

Made my own little tool to find the length to seat to lands in my rifle. Max recommended OAL is 3.34. I hit lands at 3.2715. I've retested it 4 times with same outcome

(1) I assumed that since max recommended was 3.34 that most factory 270's could accommodate that length without being jammed into the lands, I guess I was wrong,,, but then again I'm very new to this.

(2) Correct me if I'm wrong but .01 is fairly safe distance to stay off lands without fear of getting into pressure spikes.

If one is not careful with homemade tools it can lead to the bullet getting slightly stuck in the lands. On withdrawing the case the bullet can get pulled out of the case slightly and then when measuring you end up with a slightly longer COL. Could you please explain how your COL tool works so we can get a better appreciation of your measurement technique.

Also you are aware that your COL will alter for each bullet shape.

If by stating that you are very new to "this" and "this" happens to be reloading then in my opinion you should back well away from the lands. At 0.01" you are already at the point of greatly increased pressure through increased inertia.

 

[CptnAwesome]

Herer the tool I made. Smoked it with a match each time and chambered very slowly

 

[Andrew Leigh]

Hi,

It is that exact arrangement that I have picked up problems with.

Made myself a copy of Hornady gauge which works better.

Cheers