Bullet seating depth question

(i.e. I don’t do seating depth testing on a hunting repeater)
Amen to that.
The last time I worried about seating farther than the tangential break of the ogive or the crimp groove was when I was shooting a Winchester No.3 Mk.1* in .303 for service rifle competitions. The magazine is less limiting than it might seem with that configuration but it is still the most limiting factor. In the end I had to conclude the older guys were right: stick to a length that feeds well and won’t hang up during a shoot.
Quartermaster, we have some great hand loaders on here, all the thread contibutors being included. They have, however, become highly developed over years in pursuit of accuracy, and are definitely not shooting the every day Winchester M70. Beware the Ides of March! :rofl:
I agree and I also am one. I have many custom rifles and actually only 2 factory ones left of which this 270WSM is one of them. I can spend any amount of time required in pursuit of getting every bit of accuracy from a given rifle. As far as seating a bullet to magazine length and forget about it, not my bag. I thoroughly enjoy time spent working up loads and the payoff is when you have squeezed out everything that a particular rifle can attain
Torn between starting a new thread, or tacking on here.......and concluded it may further OP's agenda more if offered here.

First, in terms of my shooting ability, I place myself no higher than average. Pretty much typical of average guy trying to develop reasonably accurate ammunition for hunting purposes. For my purposes and used in my conditions, ammo that will shoot 1 MOA at factory ammo velocity is perfectly adequate for the job at hand, so that is my goal.

So you read, study and then go to work putting theory into practice. And this is what happened to me........

First up is a target that shows results of a 10 shot incremental ladder. Wasn't shooting for accuracy at all. Was focused on results over the chronograph. Didn't find a distinct plateau, and at first glance, didn't like the group I found, and really didn't like the signs of pressure I was seeing, nor the nasty recoil that was building, so this powder was quickly abandoned as a failure. Or was it? The three fliers aside, that was a 1 MOA group. Were those the loads or me? I don't know cause I wasn't paying attention.


Next group.......same rifle.......still didn't like the group. At least then. But now consider this group was shot late in the PM, dusk setting in. Target was 125 yards away, honking 20 mph crosswind blowing left to right, and me shooting from an awkward stance off a big round hay bale. And I pulled the shot that landed far right. That was on me.


Last group for this rifle........the load I settled on.......also shot by me off the bench under good conditions. Seems so much better than the others, but is it really? Case could be made that rifle did well with all three loads and any one of them would have met my objective.


Next up is a group shot with a new to me rifle. This was the last 5 rounds of a box of hastily put together rounds to be used to sight in the rifle, plus fire form the brass so I could commence load development. At first glance, not happy with what was printed on paper, but then know that the flier to the right was on me. I can recall where the scope was pointed at when the rifle fired. Move that to the left to where it was supposed to be and my load development is done. That target won't win any prizes, but the rifle is shooting fine.


And then there is this target. This was as good as it got no matter what I did. Hundreds of rounds.......and lots done to the rifle, and still no joy. Last thing I did was scrub the barrel clean, the took it to a smith who scoped the bore. What we found was deep corrosion pitting coast to coast. Years of neglect and abuse had taken it's toll. Choices are live with it..........adjust scope to move impacts up and right to cluster around the square and the rifle can still kill a lot deer inside 200 yards........or put on a new barrel to tighten that up by half.

But when examined critically, even if shot exactly as shown, deer was going down. Sometimes you have to put things into perspective.

Edit: Just realized I never made my point......which was when examining groups, do so with a critical eye. The actual groups don't say it all. For hunting ammo in sporting rifles, we are not loading or shooting for scores, but for results. If doing load development and I pull a shot, and it appears as a flier, as long as I know I was at fault, I ignore it. That is on me. Not the fault of gun or load.

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Re: seating depth

No everyone buys into this, but I believe seating depth’s effect on accuracy has more to do with how much the bullet is into the case and less to do with its relationship to the lands. As a result, I find the BTO length that shoots the best and leave it there and don’t chase the lands as the throat erodes.
I was wondering if anyone was able to get accuracy in doing this. I realize I am using up case capacity, but looking for accuracy over velocity.
Would appreciate any input from anyone has loaded in this manner.
I've been working with my son and myself with our Win. 270 rifles...Buying commercial ammo can be expensive because you have to find the stuff your gun likes. Mt son bought Fed Fusion and his rifle hated it. There was $50 out the window. So, 1) Sierra GK can explode on you if shoot them too hot. When I was using them, I kept their speed around 2800 fps. 2) When shooting all copper bullets you need to go up one size heavier to get the same terminal performance as a lead filled bullet would get. 3) Understand we shoot regular .270 Win. Figuring on run out, my 1970 push feed Mod.70 likes 3.295 with a Hornady 130 graing SPBT. My son's 2012 Mod 70 likes the 140 grain ELD-X and is seated at 3.308. Now those are based on the run out. Max is near 3.340 which give you an idea how close they are to the lands. You can do this too by loading your favorite bullet in an old case and hovering over a candle to cover the bullet with carbon , slowly chambering it. Slowly remove it from the chamber. It should push the bullet down into the case when it hits the lands and the carbon should show you where the lands actually hit. now all you have to do is back off your favorite amount a little. So I am .045 off and my son is off .032. That will change with every bullet style and weight.
Well I am not even in the same ball park as some of the shooters here, but I'm at least in the same zip code as most.

The majority of my load development has been with factory rifles. Of those I seem to have gained some repetition amongst folks I've hunted and shot with through the years as doing it right. Since most of the rifles I have and still do deal with are for hunting I use the mag length to start with. I will start out with the bullet as far out as it will rightfully function. Some of the newer sharp pointed plastic tip bullets just don't feed as well due to getting caught up on the from of the mag or bottom of the chamber lip so adjustments sometimes have to be made.

Either way, once I have the starting OAL I work up my powder charge weight from there. Once I find that, I start seating in .005" increments until everything comes together. Usually this is within about .035-.065" from the original depth, but I have seen it go up as far as .120", and that actually ended up being the book recommended length. (go figure)

Yes in most cases, especially nowadays with the longer higher BC bullets you will end up with the base back behind or below the case neck and even the shoulder. I personally don't get overly concerned with that as long as the group is there I'm good. I very rarely load to the max anymore and usually use a powder that runs around an 85% fill on the case. I did have loads for a couple of calibers years ago where I was getting up to the necks with the powder charge and then have had the powder push the bullet back up after seating. I just found that while they were accurate and had good velocity, the lesser charge weight of maybe the next faster powder would work just as well.

All that said, in the end it will be a combination of the best fill ratio, seating depth, and bullet make that will give you the tiniest group.
This old thread seems on topic.

I have a 270 WSM that I would like to try 150 gr bullets in. Currently I am shooting 130 VLD hunting which shoots pretty decently, but I’m not overly happy with the terminal performance. In working up my loads, I have used 130 gr BTs and Sierra GKs, but my rifle wasn’t crazy for either, accuracy wise despite trying all kind of variations. Not that they awful, but I want less than MOA.
I bought a couple of boxes of 150 gr, 1@ from different mfg’s, but upon seating them touching the lands, the heal of the bullet is well in the case body beyond the neck/shoulder junction. I never like to do this, but can’t say that I really ever gave this scenario a decent try.
So as to not waste my time and components, I was wondering if anyone was able to get accuracy in doing this. I realize I am using up case capacity, but looking for accuracy over velocity.
Would appreciate any input from anyone has loaded in this manner.
Thanks in advance
Maybe get a bullet comparator for your micrometer and make your handloads the same as your best shooting current load.