I followed Dan owc test in every way execept shooting round robbin. The gun was a rem 700 VLS 22-250. Powder Reloader 15 Primer fed, Bullett Sierra 50gr my col was 2.350. I had talked to Sierra tec before had & this was the powder they recomened & max charge 36.2. Here is the test charges were 34.7-35.1-35.5-35.9-36.1-36.5 first sign of pressure. I ended up with the conclusion that it made no difference I could cover all loads tested with a 1.5 circle & no group was over 3/4". I will use 36gr to start testing length as that gave me a 1/2" group & no pressure signs. Is this a fluke that all had same point of impact or did I just hit the right combination.Just for information 36gr gave me 3700 FPS.

Sounds to me like you have a good solid gun!!!

BossMoss,

When you say that you could cover all the loads with a 3/4" circle...

Do you mean that none of these charges deviated from the bullseye more than 3/8" (half of 3/4" is 3/8")?

Or are you saying that all of the charges tested shot three shot 3/4" groups which grouped in different places with relation to the bullseye?

Is it possible to post a photo or scan of the targets so we can discuss the groups?

Thanks for sharing you info,

Dan

Sorry,

I see now that you mention that the groups could be covered with a 1.5 inch circle... My bust!

Anyway, to find the OCW--if indeed it does lie within the range of powders you tested--you would triangulate all three shot groups and find the three consecutive groups which you could cover with a 3/4" circle--or 1" circle max.

Did you find three successive groups that shared a common triangulated point?

Dan

Dan, I wish I could post my target. My overall group would be under a 1" execpet for 2 shots. Today I shot 36grs & 36.5 in the same spot. What I am sating is I think I can use any charge I want & a couple tenth won't make a difference. I have a digital camera if I can get a good pitcher I will try and send it to you if you give me your email. I do like your system just thought I would see more of a difference.It is a heaver barrel maybe it will shoot anything I through at it. I just got the gun a couple of wees ago. I am interested to see if changeing length is going to make a difference.

Dan, I emaild you my target give me you thoughts.
Thanks, Troy

You're right that the heavy barrel is going to whip less, and the group movement will be less. The other issue is the relatively light recoil of the 22-250.

What you'll need to do to find the OCW is triangulate the groups, and decide which three consecutive groups went to the same place.

I realize that might be hard to tell with 3/4" groups. The rifle is likely capable of shooting 3/8" groups when all comes together.

As you come to center of the OCW zone, the group should tighten noticeably. This doesn't mean that one tight group will be the center of the OCW zone--good harmonic nodes can throw shots together at just about any point along the charge ranges. But the single tight group with a group on each side of it which hits the target in the same place (relatively) is worth noting. That may be the OCW...

My guess right now is that the OCW may be higher than you've gone so far. Speer's max is 38 grains. Sierra's maxes are normally very conservative. If you've found no pressure signs to this point, I believe I would look at 36.7, 37.0, 37.3, and 37.6 grains. Somewhere in that zone you should find that the groups will tighten, and that should make it easier to plot points of impact and thereby find the OCW.

I'll email you my email address, and you can send the target photos and I'll post them in this thread with your permission.

If you want a wildcard for the next range session, load one shot of 33 grains of IMR 4895, and one more of 33.5 grains, and then try a four or five shot group using 34.2 grains of IMR 4895 behind the 50 grain bullets. I think you'll be pleasantly surprised...

Thanks again for sharing your experiences,

Dan

Dan, Sierra said I would get 3800FPS with 36.2gr os R15 I was at 3700 so were not to far off. When I went to 36.5 the bolt opened hard not bad but hard so I feel I am close to were I should stay. It only 30deg out here so I am tring not to get to crazy as pressure and speed will go up this summer which will put me around the 3800 Sierra is saying I think. I am not sure why Speer is saying 38 I realy don't think I could get their if I wanted.We were getting about 100FPS with each 7 or 8gr. so 38gr would take me to 3900FPS I think that is getting to hot. I know you not realy big on conagraph but if you are getting the speed the load books are telling you that you are to get at lower charges you must beleave that your pressure is getting up their.

Okay, I got the target photo... Here it is:



Do you happen to have the target with the high charge--the 36.5 grain group?

Upon re-reading your initial post, are you saying that you're getting pressure signs with 36.5 grains? If so, what kind of pressure signs? I've gotten cratered primers almost routinely on the 22-250's I've worked with--though I don't know why... But no other pressure signs. Lightly flattened primers, perhaps, but nothing that concerned me.

Hard bolt lift is the biggie, in my opinion. You'll note that the Winchester factory varmint-pack 22-250 ammo flattens the hell out of the primers.

Anyway, I see that the 36.1 grain group really tightened up, which could indicate that you're on the lower end of the OCW zone. Again, I'd be curious as to where the 36.5 grain group printed.

Thanks,

Dan

(edited to reduce photo size)

[ 02-23-2003, 07:33: Message edited by: green 788 ]

Above is my effort at triangulating the groups in question. The yellow dots would be where I would place the group average centers.

The trend is moving down, and to the right slightly.

Here is the second target, plus BossMoss's text: "Dan, here is the target with the 36.5gr... 3 shots were 36 [36.1?] and 2 were 36.5 the 2 touching were the 36.6. [36.5?] But the bolt did open hard not bad but hard."


Well, I would have to say that hard bolt lift is a pressure sign not to be ignored.

The 36.5 grain shots which are touching seem to have moved the group hard to the right of the 36.1 grain shot.

I would have to conclude that the 35.5 grain charge is going to give you the most stable groups here. I don't know whether that is going to be an OCW or not. (I define OCW loads as those which give excellent results in various rifles).

The 35.9 and the 36.1 grain charges are pretty close in pressure, and come out pretty close on target.

By considering the last two groups on the page of 5 groups basically the same (due to the close charges), I would look at the common POI of the 35.1, 35.5, and 35.9 grain charges and conclude that 35.5 grains is worth a second look.

Don't forget to test the IMR 4895 as well--if you feel so inclined.

Take care, and keep us informed...

Dan

[ 02-23-2003, 08:14: Message edited by: green 788 ]

Dan, Thanks for the dots I now see what you mean a little better.I will try a different powder but am looking at makeing this work first then I will move to to something different & see if I can do better. I am going to try 35.5 and change seating depth as I said I was at 2.350 max length in the load books kknow I will work towards lands. I don't know how far I will have to go to dial it in but you are saying it will not change my OCW if I move bullett out no mater how far I go.

That's right, within reasonable limits... So long as you stay within about .035" of a caliber's depth, I'm certain that the OCW won't change. There should be more than enough depth tuning room in .035" to work from one end of the vibration pattern to the other.

The OCW is just that, the Optimal Charge Weight. Once that charge is identified, it should be left alone. Group tuning would then be done with seating depth variations.

Keep us informed...

Dan

BossMoss,
I ran your load combo through Quickload and this is what I came up with.
Max pressure for the 22-250 is...58740 psi
your load of 36.5 gr of R15 puts you at...56506psi
and your muzzle velocity should be around 3779 fps
The pressure of your load is at a critical stage. Any slight variations in your load will put you beyond the safe pressure limit. Be careful moving your bullet closer to the lands as that will raise your pressure.

Turkeyshoter, Thanks you numbers are real close as velocity at 36gr was 3700 so 36.5 should be close to what you are saying. I am planing on backing off to 35.5 and try to tune with seating depth from their. Bolt was firm to hard to open at 36.5 so again you were right on. Sierra tech said max was 36.2 but 36.1 showed no pressure so I went for a little more now it's time to back off for safty.I am intersted in what program you are useing it sounds like something I would be intersted in can you give me more info.