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Posted: 12/16/2009 12:34:13 PM EDT
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Alright Guys,
I loaded up some the following for my Savage .308 with a Leu 4.5x14 set at 14X at 100yrds off a bench 168 SMK's BH Brass 2.005" RL-15 WLR Primer OAL 2.810" As suggested from my previous post I loaded up another 50rnds and started over at 39.5 and went all the way up to 43.0 of RL-15 (making 5rnds each in .5 gn increments) and used alot of sandbags on the front end and a mono pod on the back that's built into the Choate Stock I have, I don't have a Chrono but it looks to me like the 39.5 did the best ? I started with a clean bore and fired 2 foulers then proceeded to go thru the groups of five and as I did they opened up like my first time out, I checked my Sierra manual and at 39.5gns it's not real fast but looks to be accurate. So I am asking you guys to look over my targets and offer up any advice even if it's negative 
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I'm assuming you let the barrel cool between shots/groups.
I've never shot the Savage .308. What about recoil? Are you thinking "ohshitohshitohshit" as you approach 42 grains? Using sandbags and not a Ransom Rest the shooter can contribute to the spread as well. (Or at least THIS shooter!). |
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Quoted:
Looks like that gun is a keeper. What's the center to center measurement on 39.5, 40 and 40.5? Extreme Spreads are: 39.5 = 0.720" 40.0 = 0.899 (counting flyer) 40.5 = 0.722 My Sierra manual has the min load at 38.8 but I did not go below 39.5 so I have to ask can I go down to 38.0 ? this will put me below min but I don't want to get into trouble, I figured I would go 38.0 - 40.0 in .5 increments |
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My Sierra manual shows 38.8 grains of RE-15 and the 168 gr. MK as a minimum load. You have room to go a little lower and room to go higher also. 43.6 is listed as the maximum showing 2700 fps from their 26" barrel. If you have a 24" barrel it would be approximately 2650 fps maximum velocity with this powder and bullet combination.
Your groups were begining to tighten up again on the highest charge you tried. If your primers looked good, the bolt was easy to manipulate and otherwise you had no signs of high pressure I would bump it up another .5 grain and see if it gets smaller yet. Don't go over 43.5 grains or 2650 fps from a 24" barrel, whichever comes first. |
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You messed up. If you shoot the staples out, you won't tear the targets. All you have to do is pick them up.
The only advice I have is that you need to shoot more targets with the promising loads. If you can find an accurate load over a 1 grain spread of gunpowder, settle on that, unless it's really slow. I think you need to hunt around that 43.5 grain load a little. The 41.0 and 41.5 grain targets look to me like they have a little wind or you mishandled the gun. I also think your rifle is not going to be picky about loads with that bullet. |
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Quoted:
You messed up. If you shoot the staples out, you won't tear the targets. All you have to do is pick them up. The only advice I have is that you need to shoot more targets with the promising loads. If you can find an accurate load over a 1 grain spread of gunpowder, settle on that, unless it's really slow. I think you need to hunt around that 43.5 grain load a little. The 41.0 and 41.5 grain targets look to me like they have a little wind or you mishandled the gun. I also think your rifle is not going to be picky about loads with that bullet. The Sierra Manual list the velocity at approx 2400fps at 38.8 and I was at 39.5 with a spread of 0.720" I may go down to 38.0 and up to 40.0 and check the lower end but I am not sure what the velocity would be at 38.0 as the book does not go that far down, is it safe to go that low ? |
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If you're not sure about the bottom charge, then feel you way along by reducing the charge gradually.
I think going down to see if the accuracy improves is the wrong strategy. You shot several loads, and all but two show great promise. The two that don't have flyers that probably are not indicative of the rifle's accuracy. You haven't shot enough at any of the charge weights to make a solid conclusion, what you have are some good hints so far. Since flight in the wind is so important at longer ranges, I think you should try to find out just exactly how much accuracy you have around 43.0 to 43.5 grains, and maybe out to 44.0 grains if you're comfortable shooting that load and your cases don't show distress. |
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Quoted:
If you're not sure about the bottom charge, then feel you way along by reducing the charge gradually. I think going down to see if the accuracy improves is the wrong strategy. You shot several loads, and all but two show great promise. The two that don't have flyers that probably are not indicative of the rifle's accuracy. You haven't shot enough at any of the charge weights to make a solid conclusion, what you have are some good hints so far. Since flight in the wind is so important at longer ranges, I think you should try to find out just exactly how much accuracy you have around 43.0 to 43.5 grains, and maybe out to 44.0 grains if you're comfortable shooting that load and your cases don't show distress. I am finding out load development is frustrating and fun at the same time but it's also $$ using match components but I guess that's how it goes, I have another batch made up starting out at 38.0 and up to 40.0 (5 @ in .5 increments), I may after shooting these go from 40.5 - 44.0 and compare again, once I pick a load I would assume make up say 50 and try them at a further distance Thanks for everybody's help this pinpoint accuracy stuff is still all new to me |
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Don't fall into a trap looking for the perfect load. .308 Win is forgiving, but you'll shoot the barrel out of magnums before the most perfect of perfect loads is found.
Use a rudimentary wing flag. A piece of surveyor tape flying from a stick jammed into the ground is better than ignoring the wind. Put it up about 1/4 to 1/3 of the distance to the target. Barring that, do everything you can to pay attention to even slight breezes, and try to shoot in the same condition. This chart will help you understand how the wind affects bullet flight with a little more precision that most people consider: http://www.vintagebenchrest.com/page16/files/windchart.pdf |
| Personally, I would look between 40 and 40.5. The data given shows the center of those two groups are pretty close to each other. The reason I say this is because you want consistency and a little bit of lee way on your charge weights. Of course, that's just the way I do it. Granted, this is only using the data that you've given. |
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This was the reply from Sierra:
Hi Bill, That shouldn't really be a problem in dropping on down that little of an amount,but I still wouldn't go there.Honestly I would look for your best accuracy to come on the upper end somewhere.Many,many times I've seen rifles do this. Paul> Paul So I guess with that said it's back to the Bench, I plan on going from 38.0 -44.0 and will post up the results, I guess it's a good think that I bought more SMK's, I may look at getting a rest over the sand bags to stabilize it even more but I hate to do that because I really want to shoot prone and not off the bench but for load development it may be necessary |
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You're not listening to experienced advice.
Look for a good load at the top of the range. When you stretch a shot out you will want it traveling as fast as possible to minimize the effect of the wind. Control what you can, vertical disperson, and minimize what you can't, which is the wind. Starting at 38 grains will do two things, one is bad - you'll burn up a bunch of components, and you will learn some interesting information. So I guess it comes down to how badly you want to know how your rifle will shoot across 6 grains (or more) of gun powder and the cost of the components and wear and tear on the rifle's bore. This is a rifle that shoots very nicely, so you may want to consider taking good care of it. To give this a fair trial, we're talking 325 shots. |
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What did 42.5 and 43.0 look like? How are your primers after shooting the 43.5 grain load? AeroE is right regarding the low charges. You started near the bottom, not all the way, but the velocity of the starting loads is only 2400 fps. .308 shooting 168's usually shine from 2500 fps to over 2600 fps. Some people load hotter with excellent results. I prefer this velocity range if the rifle shoots well there. According to Sierra's manual and their rifle it would be somewhere between 40.5 and 42.0 grains. YMMV.
I can't emphasize it enough when shooting groups for load work ups. You have to make perfect shots, lots of them. If one feels off at all you might as well go paste the target up and start over. You won't get the real information you need if you allow bad shots to become part of the process. This is time consuming, but worth it. |
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Okay guys I will save the components and start off at the 39.5 and go thru 44.0 and make 10@ and see what happens, I don't want to be limited to it shooting well at 100rds but crappy at 500.
The bolt was pretty easy to cycle at 43.0 and the primers looked fine but when I get these shot thru I will post up targets and brass for evaluation, and maybe if any of you guys live near Houston we can get together and go thru this 
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I wish I could make it look better proportioned
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