Help Me Read My Target

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So I made my first loads for my Savage today to see what would give a good group. I loaded 6 groups of 5 rounds each going by the book I have (Sierra). Shots are all 5 shot groups at 100 yards from the prone position (first time prone with this rifle), off a bipod, with a rear rest, slightly up hill shots. Conditions were calm winds, apx 24c. The rifle had only 20 rounds throught the pipe previous to today. I don't have a tape measure handy so I can't measure the groups right now.

The specs are:
Rifle: Savage 110BA
Brass: Lapua (once fired), body sized, and neck sized.
Bullet: Sierra 250gr HPBT Match
Primer: CCI 250 LR
COAL: 3.681

I used 3.681 because that's what the book says. I have yet to find out where the lands are. I have to make a dummy round friday but I want to narrow down the group before I start playing with COAL. As you will see in the pictures I think I should focus on groups 3 and 4 and load up another batch breaking down the spread between the groups.

Pressure signs: After shooting group 5 I noticed very slight cratering in the primers. This was also evident in group 6 but was not any worse than the cratering in group 5. There was no noticable change in the force to lift the bolt from groups 5 and 6 from any other group shot (they all felt the same).

I am most currious about the vertical dispersion versus the horizontal dispersion in group 4.

I'm new to this whole precision thing and am trying to learn. I have some US869 as well but am having trouble finding load data for it with 250gr slugs. I plan on getting some 300SMK's soon since I hear people have been having good luck with them with the 1 in 9 twist.

Thanks!

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I'm not sure that a great deal can be learned from those groups. All seem to be running 1 1/4 to 2 minutes. Single five shot samples with each load don't really tell too much.
With a different rifle of known accuracy, what sort of groups do you usually shoot?
 
Unfortunatly my other rifle is a M44 and a .22 with not much accuracy between them. I under stand what you mean though, it's hard to to guage because you do not know the shooters ability but everything else being equal, the spreads are fairly consistant. I have done alot of reading and watching on proper shooting position, being behind the rifle, sight picture, loading the bipod. I would hold on target and close my eyes for a few seconds then reopen them and i'd still be on target, if I was not I would adjust my position. I felt confident on all but one shot (the shot on group 6 right above the 6). I don't really have a baseline for what groups I usually shoot. I definatly need more trigger time behind the rifle, and will be going out again on Friday. If you have any more questions or comments, please say so.

Thanks,
PA
 
I agree with tiriaq, not much to tell with those groups, I dont mean to be rude in anyway, maybe a suggestion if I were in your shoes i would get a couple boxes of factory ammo all being the same. say 2 boxes 40 rounds so 8 groups at 5 rounds each. all being the same round, then you would be able to verify two things, 1 your consistency, and how well the rifle shoots with factory ammo, because generally when your using higher end rounds like the sierra's your groups should be tighter than those of factory ammo.
and that would give you more practice with trigger control.
my 2cents hope it helps
 
You certainly are on the right track, you're aware of what needs to be done.
I'm not sure that loading the bipod is the way to go, I know I don't; I use Harris bipods. Without loading, the rifle is in neutral, so to speak. If loading, the pressure would have to be the same every shot. Easier to be consistant with no load.
As a beginning precision rifle, I think you have picked one of the more challenging ones, from the standpoint of cost, recoil. What scope are you using?
There is a real techinique to firing perfect shots from a bipod with a bag under the toe. A meaningful group forms when a series of perfect shots are fired.
 
As I read it, all of your groups are about the same (by eyeball I see them as essentially 1.5 minutes, plus or minus a quarter of a minute). This tells me that a certain level of consistency has been achieved (by you + your rifle and scope + your ammo). Also I see that there is not any meaningful difference in accuracy across the entire range of powder charges that you tried. Also, in your shooting of these groups you did not throw any seriously bad flyers (from looking at these groups I can't tell if your shooting technique is good enough to produce half-minute groups - but I can tell that it is good enough to avoid firing 2 MOA groups).

At this point with everything so new, it is hard to say if there is a problem or not, and if so what it might be. Here are various possibilities:
- this particular rifle is not capable of shooting better than 1.5 MOA (your scope might be loose or bad, your rifle's bedding screws might not be tightened, there might be something wrong with your bedding action or barrel)
- the particular ammo you made is only good for 1.5 MOA
- your shooting skills and technique you used are only good for 1.5 MOA

Figure out a way to knock off one or more of these. For example if you have a friend with a known-accurate rifle, you could mount your scope on his rifle and shoot a few groups; if you get good results then this shows that you are able to shoot and that your scope internals are fine. Or buy some factory ammo (ugh!) or find out some known-good handload combination that works in nearly every .338 and try that in your rifle. Or try your ammo in another known-good .338 rifle.
 
FWIW, I'll put my 2 cents in for changes based on what I'm seeing.

- make your powder load increments smaller, go up in 0.3 or 0.4 gr per group.
- remove bipod for now, shoot from front and rear bags.
- figure out you COAL for that bullet, go to a .020 jump to the lands.

After that if you're still not seeing grouping differences,
- Try different powders with that bullet.
- Try different bullets.

Steve
 
I'll see what hapens on Friday when I go out again. I am going to focus on between 92.5-96.5gr and load up about 25 rounds and see what happens. I'll also make a dummy round tonight and figure out where the lands are and try to have them so they are just touching the lands. When I shot those groups, when I closed the bolt there was some resistance so I think there was a bit of a jam into the lands. We'll see. I'll post some more targets Friday.

Thanks for all the advice and comments though. Don't think I will be offended, I have big shoulders.
 
If I might suggest, once you find where your lands are, load your ammo so that it is about .020" shorter (i.e. about .020" jump to the lands). It is *much* more convenient to handle a round if it does not jam into the lands, and Sierra matchkings are usually pretty tolerant of a bit of jump. Oftentimes one can get really good results with a modest amount of jump like this ("good results" as in match-winning accuracy). Loading really near the lands or jammed into the lands is really pretty fussy business; sometimes it is necessary in order to get best results, but it's nice if you are able to avoid it

FYI the Hodgdon online load data has loading data for US869 for a 250 HDY SP, which suggests that perhaps another 40fps more is available over H1000 (not that that would be a good reason to choose one powder over the other).
 
You might be flinching a little, although your groups are pretty consistent, and flinching usually gets worse as a session progresses, but you might ask someone to make sure you aren't flinching. That would eliminate one variable. A 338 is a big honkin' gun.
 
When I was shooting I would catch my self flinching every so often, usually on the first shot of each 5 shot string but I would catch my self before firing. So I would back off, breathe, relax and try again. I followed through after each shot and after the recoil was over, I was still holding on target, not excactly where I was aiming but still on the paper. I tried to be as meticulous as I could about my position, breathing and trigger control. When I fired the first 20 shots out of the rifle after I had first got it, I was shooting off the bench. I was getting all sorts of hop. When firing prone it was much more controllable, I could feel the rifle recoiling strait back and not jumping around like on the bench.
 
A test to see if it's the nut behind to trigger is to let somebody else shoot some groups with it. A couple would do. It could be something you are doing wrong.....and can learn to fix.

You said you have an M44 and a 22. What 22, are you sure it is not capable of some good accuracy. I would be the cheapest and easiest rifle to use to practice technique.

With you big boy, you could practice dry firing at home. Make sure that your reticle stays on your point of aim as the trigger breaks.

Of course, the nut behind the trigger could well be fine :)
 
Thanks Bolivar, the .22 I have is a 597 Viper:redface: I have pratcied at home dry firing, placing a quarter on the muzzle, position. I just hope i'm doing it right.

I made a dummy round to find out where the lands were and checked it 10 times and took the average of the coal, came to 3.733. My other rounds I loaded were loaded to the book specs of 3.681, a difference of 52 thousandths so i'll load the next batch up at 3.723 and see what happens.

I think it's supposed to rain here on Friday but if it's looking good after work i'll head out again and post up some pics.

Wish me luck (or skill) :)

PA
 
Interesting that your measurements indicate you were jumping the bullets about 50 thou - in which case the stiffness of closing the bolt would not have been due to the bullet engaging the lands. Any idea why you were getting resistance? If you chamber a piece of brass (before you put a bullet in it), does it chamber more or less effortlessly or is it pretty snug?

I have no idea about the level of your shooting or reloading skill, so please accept my apologies in advance if I guess or assume wrongly. FWIW from reading your post #11 it sounds to me like you have a fair bit of experience shooting. Do you have previous shooting experience with different rifles in which you are able to consistently produce 5-shot groups significantly smaller than the minute and a half that you're getting now? If so then we can assume that you out as the reason for these 1.5 MOA groups. If your shooting skill is not a known good factor then either you can get a known-good shooter to fire your rifle, or you can shoot a known-good rifle and then know what your current skill level is.

Re: the Hodgdon data being for Hornadys and you are using Sierras, that is OK. Published reloading data is never an exact fit for your rifle anyway (for example your barrel and chamber are almost certainly somewhat different than their test gun). Published C.O.A.L. should be looked at as an interesting piece of information but it is nothing like a "rule" w.r.t. how long you should load your ammo. You are already correctly dealing with the Sierra bullets in your chamber.
 
When closing the bolt on some rounds, the effort required to close the bolt was stiffer than others. I by no means had to really put my weight into it but it was noticable. I understand what you mean and thought the same thing my self when I found out where the lands were (why would there be resistance when it's a 50 thou jump to the lands). I checked the legnth of all the brass with the spent primers out before loading and they were all under max case legnth according to my sierra book. They were all body sized and neck sized.

The method I used to check the lands is I took a once fired (from my rifle) brass, cut a slit down the neck but not into the shoulder so that a bullet (the same ones i'm loading) would be held in just tight enough to slide in and out but would not be pulled out when extracting. I put the bullet in and measured it to make sure it was seated plenty long, then chambered it and measured it (10 times) and came up with 3.733.

I loaded up 20 rounds last night seated at 3.723 (.010 jump) in .3 (or .4, cant recall right now) increments. Every load was measured, every bullet was gradually seated to that legnth so it should be fairly consistant. I am going back out today after work and will post the results. I do have a front bag I can use but I fill mine with airsoft bb's. I need to get some more to fill it completly and the nearest store that has them is 1 hour away so it's still bipod for now untill I can get some more.

Thanks,
PA
 
Sounds like you're well on you way to finding some good loads now.

You mentioned that you "gradually seated" each bullet, you should be able to push them all through with the same setting. The COAL will vary some as the bullets themselves are not uniform from ogive to tip, some worse than others and you shouldn't adjust based on total length. As long as the ogive to lands distance remains fairly constant it should not effect the groups.

Steve
 
Ok, that is why I gradually seated each one of them because I wanted them all the same legnth. How will the bullets be most uniform? From the base to the tip or from the ogive to the tip? I'm using the Forrester micrometer bullet seating die which from what I understand seats by pushing on the ogive of the bullet. We'll see I guess.

PA
 
Base to ogive would be the correct measurement but don't worry about it right now, just keep them a fair bit off the lands for the time being and see how the shooting goes.

Steve
 
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