Developing .243 varmint load - which way to turn?

[barnfrog]

Without starting a debate about whether to start with charge weight or seating depth, I'm looking for some friendly advice.

I loaded up some Sierra 60 grain hollow points over 42.0 grains of Varget and seated them at 0.020", 0.030", 0.040" and 0.050" off the lands of my Winchester XPR .243. One thing I noticed when working up the seating depths is the bullets aren't very far into the necks. The ones with 0.020" of jump are only 0.161 in. Case lengths are 2.040", so they haven't been trimmed back excessively. I realize the "seat at least as deep as the bullet diameter rule" is not hard and fast, but thought I would note it anyway.

100 yard results are shown below.



Not as good as I was hoping, but not abysmal. So, as is typical of folks like me who don't have a ton of experience, I'm curious what others might do here. Assuming a five-shot group confirms 0.050" relicates that performance, there are three primary options I am considering trying next:

1. Load an OCW test seating the bullets 0.050" off the lands to see what effect charge weight has on things.

2. Load a few more rounds at 42.0 grains and keep increasing seating depth in 0.010" increments.

3. Try another seating depth test with another powder. This was my first loading with Varget, whereas IMR4350 has shot quite well with other bullets in this gun, although none lighter than 75 grains.

I'm sure I'll get responses supporting each option, and probably some suggesting one or two others. I guess I could try all three routes just for fun.

Would love to hear anyone's thoughts (except the ones saying I should have started with charge weight instead of seating depth ).

 

[TEXASJD]

Top left group has some promise looks like it wants a little more powder round groups tend to show that it wants more pressure.

 

[Howa 9700]

I"m not far enough along to have gone for seating depth yet, but from what I've read, the test increments are a lot finer than .01........I've seen .003 to .005.

So what is the ideal increment to use for these?

 

[barnfrog]

I"m not far enough along to have gone for seating depth yet, but from what I've read, the test increments are a lot finer than .01........I've seen .003 to .005.

So what is the ideal increment to use for these?

In my admittedly limited experience, I've found 0.010" to be fine enough to get me in the ballpark. Could try fine adjustments once I'm in the right neighborhood. Some argue 0.010" is too coarse and can cause you to skip over a good seating depth.

 

[Blue68f100]

I find the OAL that Sierra recommends works very well once you do the load workup. I always wait till I have load worked up before I start adjusting the OAL I normally jump in 0.003"-0.005" steps. Then I test primers after the OAL has be tweaked.

 

[AJC1]

I"m not far enough along to have gone for seating depth yet, but from what I've read, the test increments are a lot finer than .01........I've seen .003 to .005.

So what is the ideal increment to use for these?

It depends on who you're following. I use the Berger method and then fine tune. The process looks something like course, ocw fine then regular tune tweeks.

 

[Skeptic13]

Why are you only testing Varget at 42 gr. The range according to Varget for 60 gr bullets is 40 to 42.7. I would first test different powder charges at the recommended COL and then when you find a good powder charge fine tune you load by testing different COL.

Sorry didn't see your note that you don't want to start discuss different powder charges but you didn't address why you chose 42 gr and I think it is important to give good feedback.

 

[barnfrog]

Why are you only testing Varget at 42 gr. The range according to Varget for 60 gr bullets is 40 to 42.7. I would first test different powder charges at the recommended COL and then when you find a good powder charge fine tune you load by testing different COL.

Sorry didn't see your note that you don't want to start discuss different powder charges but you didn't address why you chose 42 gr and I think it is important to give good feedback.

My mistake. These were loaded at 40.0 grains, not 42.0. Sierra's data shows 39.7 to 43.0 and Hodgdon says 40.0 to 42.7. So I started near the bottom of those ranges.

Sierra's recommended COAL of 2.600" would put these right about at 0.040" off the lands in this gun.

 

[JFrank]

If you feel comfortable at .050 off then go ahead and run a charge ladder.

 

[Varminterror]

I’m not convinced any of those groups are statistically conclusively different from one another.

Charge weight tuning goes first, then seating depth.

Shoot your OCW test at 300yrds, and if your groups are that large, shoot a lot more than 3 shots per group.

 

[red rick]

I agree with Varmin , charge weight comes first .

 

[barnfrog]

I’m not convinced any of those groups are statistically conclusively different from one another.

I'm not convinced they are, either. But so far I have started my load development with three-shot groups and that's been enough to get me pointed in the right direction.

Charge weight tuning goes first, then seating depth.

I guess you just had to get that in there.

Shoot your OCW test at 300yrds, and if your groups are that large, shoot a lot more than 3 shots per group.

There is no place I will be hunting with these loads that will afford me a shot greater than 200 yards. If I can find a load that shoots 0.75 MOA or better out to that distance I will be confident that I can do my part to reduce the crow and woodchuck population.

 

[barnfrog]

I agree with Varmin , charge weight comes first .

I should have known better than to think this wouldn't happen.

 

[FROGO207]

Might want to try a heavier bullet as well as other propellants. The lengths that the bullet manufacturer used are always a good starting point. My 243 likes 100 grain boat tail bullets the best. It is a H&R SB2.

 

[CarJunkieLS1]

Left and right spread is seating depth, up and down is charge weight. None of those groups look exactly promising to me.

 

[lordpaxman]

Would love to hear anyone's thoughts (except the ones saying I should have started with charge weight instead of seating depth ).

Assuming a five-shot group confirms 0.050" relicates that performance, there are three primary options I am considering trying next:

1. Load an OCW test seating the bullets 0.050" off the lands to see what effect charge weight has on things.

I’ll vote for #1, and I’m not starting a debate on charge weight vs seating depth first, but it’s your first choice and I agree with it. I too use OCW first, and have found in my rifles with my loads seating depth didn’t miraculously tighten up groups. Good luck.

 

[barnfrog]

Left and right spread is seating depth, up and down is charge weight. None of those groups look exactly promising to me.

Well, that's kind of why I included the option of switching to another powder, most likely IMR4350 or H4895. Just not sure I should give up on the miracle powder Varget yet.

 

[barnfrog]

I’ll vote for #1, and I’m not starting a debate on charge weight vs seating depth first, but it’s your first choice and I agree with it. I too use OCW first, and have found in my rifles with my loads seating depth didn’t miraculously tighten up groups. Good luck.

I wouldn't call it miraculous, but the last load I worked up I started with 42 grains of IMR4350 under a 75 grain HPBT and loaded five groups from 0.010" to 0.050" off the lands. Each group got successively smaller from 2.4" to 0.6". The smallest group replicated so I called it good enough. Probably pure luck that I happened to choose a good powder charge. Probably could have tuned in smaller groups with powder adjustments, but it was fine for my purposes. I'm not deluding myself into thinking it will go that easily every time, but sometimes it works.

 

[Varminterror]

There is no place I will be hunting with these loads that will afford me a shot greater than 200 yards.

Then OCW method isn’t the right method for your load development process.

If that target was my first round of load development with a 3/4moa goal, I’d turn 180 degrees and seek a different powder or bullet or both.

 

[243winxb]

243 Winchester- The Sierra #1530 85 gr hpbt pushed with IMR 4350- 42 grs, BR2 Primer, Win or Rem brass, OAL 2.640" should get you 1" @ 100 yards. Work up. A 1/2 gr more or less may make a difference?

Don't try to reach the rifling by using a long COL. The full diameter bullet shank should be near the neck, shoulder junction.

H4350 can be used also, but requires more powder.

 

[243winxb]

42 grains of IMR4350 under a 75 grain HPBT

IMR 4350 & 68 GR Berger FB @ a maximum loading has done 1" @ 300 yards.

Both IMR 4350 OR H4350 do well.

A 90 gr HPBT Match Berger likes IMR 4831. But is sensitive to the powder charge & lot number.

 

[Virginia Jim]

Charge weight or seating depth?
When you come to a fork in the road, take it.

 

[Bfh_auto]

Without starting a debate about whether to start with charge weight or seating depth, I'm looking for some friendly advice.

I loaded up some Sierra 60 grain hollow points over 42.0 grains of Varget and seated them at 0.020", 0.030", 0.040" and 0.050" off the lands of my Winchester XPR .243. One thing I noticed when working up the seating depths is the bullets aren't very far into the necks. The ones with 0.020" of jump are only 0.161 in. Case lengths are 2.040", so they haven't been trimmed back excessively. I realize the "seat at least as deep as the bullet diameter rule" is not hard and fast, but thought I would note it anyway.

100 yard results are shown below.

View attachment 1023916

Not as good as I was hoping, but not abysmal. So, as is typical of folks like me who don't have a ton of experience, I'm curious what others might do here. Assuming a five-shot group confirms 0.050" relicates that performance, there are three primary options I am considering trying next:

1. Load an OCW test seating the bullets 0.050" off the lands to see what effect charge weight has on things.

2. Load a few more rounds at 42.0 grains and keep increasing seating depth in 0.010" increments.

3. Try another seating depth test with another powder. This was my first loading with Varget, whereas IMR4350 has shot quite well with other bullets in this gun, although none lighter than 75 grains.

I'm sure I'll get responses supporting each option, and probably some suggesting one or two others. I guess I could try all three routes just for fun.

Would love to hear anyone's thoughts (except the ones saying I should have started with charge weight instead of seating depth ).

I'm surprised no one has said the at least one seating depth in the case neck is necessary for an accurate load.
I was attempting the same thing you are with a 270 using 90 gr bullets.
Someone suggested seating to at least one cartridge length in and my groups tightened up. Until then I had a steady 2 touching one flyer issue.
If I'm seating far from the lands. I just load groups of 3 in .3 grain increments and shoot it. The bad loads usually does themselves in 3 shots. The potential loads can be reconfirmed with multiple groups.

 

[JFrank]

@barnfrog
I get that you are qualifying /course seating depth first and that's fine as Berger suggest the same when using VLD bullets as the optimum depth can go from .020 jam to .120 jump but once you have a basic depth i assume you will move towards charge increments then return to fine tuning of the seating depth.
Please report back your results
J

 

[barnfrog]

Thanks to everyone who chimed in, even (maybe especially) those who have offered advice I don't really want to hear. Debates about things like powder charge vs. seating depth remind me of listening to dueling economists; everyone sounds like they know what they're talking about, which can make it tough to know who's right. Sometimes they both are.

At this point I think I will try some form of charge ladder (perhaps not strictly an OCW test) and also load two or three more 40.0 grain groups in 0.010" increments, and if none of the results shows any promise I'll try switching to IMR 4350. That should have me thoroughly confused.

To be continued.....