If you don't seat at a least a bullet width in the case. You will be wasting your components.
If you want close to the lands switch bullets.
Developing .243 varmint load - which way to turn?
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If you want close to the lands switch bullets.
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barnfrog
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Distance to the lands is not the goal. Consistent, precise and accurate groups is the goal.
At the risk of going on a rant, this is yet another example of conflicting advice that is so aggravating to new reloaders. If I seat these bullets at least one bullet diameter into the case neck, I'm 0.060" shorter than the manufacturer's listed COAL, which lots of folks say is the best place to start. Both may be valid advice, but if I can't do both, which is more important? (That's a rhetorical question, by the way. No need for anyone to answer; it would just perpetuate an unending debate.)
At some point I'll have my own process down, and then I can give the conflicting advice based on my years of experience, I guess.
Varminterror
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The 1 Bullet dia seating depth is a generic rule of thumb with almost no validity or relevance in practice. Some cartridges won’t even offer enough neck length to allow one full Bullet diameter of contact - for example 300wm with only 6.5mm dia worth of neck length. With flat base bullets, we hear all kinds of experience based lore about seating the pressure ring no deeper than the sizing die travel, keeping the base of the bullet no deeper than the neck/shoulder junction, or seating boattail bullets with the bearing surface no deeper than the neck/shoulder junction. I shot groups in the .2’s with virtually no load development and only 77thou bearing surface in the neck of one of my 6 creed barrels - throated for 115’s but shooting 105’s 8 thou off of the lands.
It’s far too easy to break that rule of thumb and still have what most consider extreme success to believe it really carries any weight.
It’s far too easy to break that rule of thumb and still have what most consider extreme success to believe it really carries any weight.
JFrank
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Sorry......
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barnfrog
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No apologies needed from anyone. I understand that everyone who responded did so with the intent of being helpful. I apologize if any of my responses have seemed ungrateful.
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barnfrog
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Well, here's some follow up. Ran a charge ladder up to 43.0 grains over the weekend. Here are the resulting groups.
That small group at 42.0 grains sure looks enticing, and I'll load up another five rounds to see if it repeats, but the POI shifts above and below that charge have me pretty well convinced it will prove to be a fluke.
I also tried three more groups at 40.0 grains, seating the bullets at 0.060" to 0.080". Still nothing to write home about, but the 0.080" group was under an inch so might be worth a five shot group just for kicks.
Were I a gambling man, I'd wager I'll be switching to IMR4350 in the very near future to see how well it works with these bullets.
That small group at 42.0 grains sure looks enticing, and I'll load up another five rounds to see if it repeats, but the POI shifts above and below that charge have me pretty well convinced it will prove to be a fluke.
I also tried three more groups at 40.0 grains, seating the bullets at 0.060" to 0.080". Still nothing to write home about, but the 0.080" group was under an inch so might be worth a five shot group just for kicks.
Were I a gambling man, I'd wager I'll be switching to IMR4350 in the very near future to see how well it works with these bullets.
Am also loading for 243 Win, so have been following this thread with interest. Was going over some load data yesterday and went back and read the powder suggestions in the Hornady reloading manual. For some reason, I was of the opinion that powders used in 243 were closer to those used in 6mm Rem, 270 Win, etc, with IMR4350 being one of the most often mentioned powders used. But that seems to be for the heavier bullets I'm loading for, like a 100 grain Interlock. Was surprised to see how many of the faster powders typically used for a 308 started showing up in the data for the lighter bullets in 243 Win. Varget, IMR 6064, 4895, etc. Not what I had come to expect.
Another thought......when going through the manuals, it is remarkable to me how many calibers there are that load 6mm bullets, and likely there is a range of bullets for each caliber that are optimum, but just because they fit the case neck and you can load one doesn't mean you should try. First caught wind of this some months back when a guy on a different forum was complaining that the heavy 105 or 110 target bullets he bought for a 243 Win were not going to stabilize with his 1:10 twist 243. Same thing probably exists on the low end too. Pretty sure that would be the case with me trying to load a really light bullet in a 6mm Rem with 1:9 twist.
Another thought......when going through the manuals, it is remarkable to me how many calibers there are that load 6mm bullets, and likely there is a range of bullets for each caliber that are optimum, but just because they fit the case neck and you can load one doesn't mean you should try. First caught wind of this some months back when a guy on a different forum was complaining that the heavy 105 or 110 target bullets he bought for a 243 Win were not going to stabilize with his 1:10 twist 243. Same thing probably exists on the low end too. Pretty sure that would be the case with me trying to load a really light bullet in a 6mm Rem with 1:9 twist.
lordpaxman
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For the heavier bullets, I’m using H4350SC. It meters well and produces some very small groups. Good luck.
Are you shooting a Sporter barreled rifle?
If so. Those POI shifts on either side of 42.0 would not be terribly surprising.
JFrank
Member
Since you're asking for input, can you please refresh me on your barrel twist?
Is this a bolt action ?
Are you using a steady front rest?
Are you using wind flags?
How much bullet hold/neck tension are you using?
Are you seating to magazine length?
Have you ran a one shot ladder to bolt lift pressure?
Is this a bolt action ?
Are you using a steady front rest?
Are you using wind flags?
How much bullet hold/neck tension are you using?
Are you seating to magazine length?
Have you ran a one shot ladder to bolt lift pressure?
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barnfrog
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Rifle is a Winchester XPR bolt action gun with 1 in 10 twist rate and 22" barrel. I am shooting off front and rear bags, not using wind flags. Bullets are seated 0.050" off the lands, which is shorter than mag length. Have not worked up to max pressure.
JFrank
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Nothing wrong with that rifle but the lack of wind flags will always add a layer of uncertainty, hang some ribbon from a tree if you have to as wind can and will blow rounds out or into a group as in your last attached targets the best group may not repeat and why should it ? The groups on each side are not even close suggesting scatter node or really windy day.
I would change bullets, to perhaps 70 ish gr sierra's and put them at least to mag length or just off the lands and run a two shot ladder to pressure then evaluate.
To add another point; ensure you have plenty of bullet hold and consistent neck tension, I know it sounds cool to have .001 or .002 but the fact is light hold can cause erratic groups whereas a bit extra doesn't hurt up to a point where it does.
I would change bullets, to perhaps 70 ish gr sierra's and put them at least to mag length or just off the lands and run a two shot ladder to pressure then evaluate.
To add another point; ensure you have plenty of bullet hold and consistent neck tension, I know it sounds cool to have .001 or .002 but the fact is light hold can cause erratic groups whereas a bit extra doesn't hurt up to a point where it does.
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barnfrog
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Sorry Jim, I realized I didn't answer one of your questions. I don't know what my neck tension is. The brass is once-fired Winchester cases that were fired in this gun and full-length sized with RCBS dies, if that helps.
The day was not terribly windy, under 5 mph. I realize that's still strong enough to affect groups, though. My "shooting range" is the draw behind our barn, which does shelter it some from the wind, but could also create some swirling effect.
I suppose it's also worth adding some context about the shooter. Up until a couple years ago I was one of those guys who got the gun out a week before the season and took a couple shots to see if it was still sighted in OK. So I am not very experienced at shooting from a rest. I have been doing a lot of dry firing, so I think my trigger technique is a lot better than it used to be, but I ain't no competitive shooter, if you know what I mean.
The day was not terribly windy, under 5 mph. I realize that's still strong enough to affect groups, though. My "shooting range" is the draw behind our barn, which does shelter it some from the wind, but could also create some swirling effect.
I suppose it's also worth adding some context about the shooter. Up until a couple years ago I was one of those guys who got the gun out a week before the season and took a couple shots to see if it was still sighted in OK. So I am not very experienced at shooting from a rest. I have been doing a lot of dry firing, so I think my trigger technique is a lot better than it used to be, but I ain't no competitive shooter, if you know what I mean.
JFrank
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Your probably ok on bullet hold with a non bushing die, I mentioned it because it's something to be aware of' the bags work well also so now just hang some ribbons or Toilet paper so if a shot goes side ways or slips out of the group you'll know why.
One shot course ladders are good for initial testing to find pressure or narrow down an area but can be tricky to interpret, where two or three shots gives a better example of load tendencies.
Ladders to pressure ensure you know when to stop.
One shot course ladders are good for initial testing to find pressure or narrow down an area but can be tricky to interpret, where two or three shots gives a better example of load tendencies.
Ladders to pressure ensure you know when to stop.
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barnfrog
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I have generally stayed away from pushing to max pressure, out of an abundance of caution. I don't have any desire to find maximum velocity if I can find an accuracy node at a lower pressure. I don't think I've ever experienced sticky bolt lift. The most obvious pressure sign I've seen in my short handloading is some mild primer cratering. I get ejector marks on factory ammo and starting loads, so I only look to see when it starts to get more pronounced.
My three-shot ladder is intended to find a good group as well as look for pressure signs. Other than saving bullets, is there a reason not to do both in the same exercise?
My three-shot ladder is intended to find a good group as well as look for pressure signs. Other than saving bullets, is there a reason not to do both in the same exercise?
JFrank
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Just barrel life and components when roughing or qualifying components. I use three shot with an abbreviated ladder in a slightly different format myself. Thats a different topic..
A lot of times the most accurate node is a high node
A lot of times the most accurate node is a high node
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barnfrog
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Well, my highest charge was at the upper end of published ranges, but the primers have looked the same all the way up and no bolt lift issues so I suppose I could keep working up just to explore that avenue.
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barnfrog
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I don't wish to be argumentative, but in retrospect I'm wondering why you feel this way. I just re-read Dan Newberry's instructions on the OCW method (https://www.twincityrodandgun.com/docs/Dan Newberry - OCW.pdf), and he specifically indicates the first set of targets should be set up at 100 yards. After shooting your groups and analyzing them he says to confirm your best load at whatever your maximum range will be; he doesn't say there is any minimum range the method can be used for.
Again, not trying to argue, just interested what your thinking is.
I agree with you on OCW for your usage.
I don't agree on your seating depth ideology. But that is a different thing.
You could always test your load at your max range. If it's acceptable don't waste components until they become more readily available.
In hunting your primary issue is your ability to make hits in field position. A 2 MOA load really is enough if you're only shooting 200 yards.
JFrank
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I think that may have been a tiny touch of sarcasm on his part. all of the different methods, Shatterlee, Newberry, Blainey or my Hillbilly version of the Deep Creek tuning arrive at the same conclusion. At least from what I have seen point of impact without vertical shifts leads the way forward weather by FPS or on paper.
Qualified components help the process, case in point my SIL wanted an alternative load for his 270 WSM unfortunately the powder /bullet combo never got smaller than a couple inches so after a couple of short ladders he had to call No Joy and move on.
Qualified components help the process, case in point my SIL wanted an alternative load for his 270 WSM unfortunately the powder /bullet combo never got smaller than a couple inches so after a couple of short ladders he had to call No Joy and move on.
Varminterror
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No sarcasm from me at all. If the shooter is working on 100yrd load development, long range development methods like OCW simply don’t apply.
1) OCW method is meant to predict long range behavior, not a short range development method, and 2) I don’t believe the OCW method, or any POI based long range load development method, is always honest when shot at 100yrds.
I’ve done different LR methods side by side, back to back, and range by range. Everything aligns at the same conclusion when shot at long range, whereas shooting different methods side by side at short range can reveal different results, OR shooting the same test in duplicate at short range can produce varying results. It seems at least 300yrds is needed to let the POI dispersion begin to outweigh the mechanical dispersion influence of short range shooting. The only long range load development method I have witnessed to produce consistent results, regardless of range, is the Satterlee method - which is to acknowledge, this method doesn’t require any target at all, as there’s no quantification of POI dispersion or group size included in the method. You could shoot all of the method into a pond and still end up with the same results.
I’ve also shot various methods at short range, and frankly, I’m not convinced any of these long range methods are remotely applicable for 100/200 yard shooting. When I can shoot a long range test which shows my charge weight spans 2-3 nodes, but all of the shots would fall within 1/2-3/4” at 100yrds (with the smallest of any individual group in the .2-.3” ballpark), it belies a lack of correlation between short range POI and long range consistency.
So no, if the OP is looking for 100-200 yard performance, I don’t think OCW is the proper rock to turn over.
1) OCW method is meant to predict long range behavior, not a short range development method, and 2) I don’t believe the OCW method, or any POI based long range load development method, is always honest when shot at 100yrds.
I’ve done different LR methods side by side, back to back, and range by range. Everything aligns at the same conclusion when shot at long range, whereas shooting different methods side by side at short range can reveal different results, OR shooting the same test in duplicate at short range can produce varying results. It seems at least 300yrds is needed to let the POI dispersion begin to outweigh the mechanical dispersion influence of short range shooting. The only long range load development method I have witnessed to produce consistent results, regardless of range, is the Satterlee method - which is to acknowledge, this method doesn’t require any target at all, as there’s no quantification of POI dispersion or group size included in the method. You could shoot all of the method into a pond and still end up with the same results.
I’ve also shot various methods at short range, and frankly, I’m not convinced any of these long range methods are remotely applicable for 100/200 yard shooting. When I can shoot a long range test which shows my charge weight spans 2-3 nodes, but all of the shots would fall within 1/2-3/4” at 100yrds (with the smallest of any individual group in the .2-.3” ballpark), it belies a lack of correlation between short range POI and long range consistency.
So no, if the OP is looking for 100-200 yard performance, I don’t think OCW is the proper rock to turn over.
JFrank
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Are you saying the Op just needs to use a chronograph and disregard the target?
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barnfrog
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Thank you for taking the time explain your reasoning. I appreciate you trying to help.
Varminterror
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Nope. Because Satterlee velocity curve method is not a short range load development method.
I thought I had made this painfully clear, but - I am saying the OP is shooting short range, so they should use a short range development method, recognizing that Newberry’s OCW, Chris’s OBT, Audette’s Ladders, and Satterlee’s Velocity Curve Methods are NOT short range load development methods.
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