I got the Hornady's in the other day and had a few hours to play with them last night. I went ahead and started with 47gr of H414 and played with OAL instead. I found that the Hornady's have a significant ogive difference than the Sierra's, and when touching the lands the OAL was 2.835".
That was kind of interesting to me, because Hornady's factory ammo I have measures 2.760" on average. Which means, on average, the factory ammo jumps ~.075". It was shooting around an inch for me pretty consistently.
I started with a .020" jump and shot a decent group but it was 3/4" left POA. Then I decided to play with OAL. Loaded 3 more .005"(.015" off lands) longer and only shot two before I realized longer was not the ticket. Then I loaded .025" off the lands and got a good group, same size as the first, but almost an inch lower than the first. And on top of that I recorded a velocity increase of 50fps.
Next load was .030" off, opening up some. And next .035", which opened the group more. Very interesting experiment for sure.
So I got a question. I'm sure with more testing I'll see a pattern or something, but maybe someone already has seen a correlation.
I have the rifle zeroed 1" high at 100 yards right now with the factory ammo. It is the same bullet I am using, 139 grain flat bases. They were average 2575fps. *On a side note this was back when I was recording 10' from the muzzle instead of my 15' so I am not sure if those numbers would be any different now, ie. if muzzle blast was effecting the previous readings.
I also found a load with the Sierras that also group around 1" high. They have a little faster velocity though, around 2600fps average.
Now I find that with the 139gr Hornady's I am loading I am getting over 2600fps average, but they are grouping almost 1 1/2" low.
I realize that different loads come out of the barrel different ways. And the reason is different powder/bullet/OAL combinations, but has anyone seen this and found something out about it?
I did not have time to test out farther, I plan too on Friday. I'll just be curious how they do at 150-200 yards. The factory ammo was doing real good at 200 yards. The Sierra's were a little more open/scattered. I do have to say that I am not going to try and chase clover leafs though. I do not doubt that they are possible, but I am fine with 1" at 100yards if I can see that the load will consistently hit in that same area - as long as the longer range also proves to be decent of course.
It is a hunting rifle after all and I have zero intention of ever shooting competitions with it. I just want to feel confident in the shots I take on game and know that if I miss it was because of me and not the rifle/load.
This article deals with temps effecting velocity, but what I was experiencing last night was just a velocity change. I guess that 50fps, or more, change was the cause of the drop. Makes me even more curious how it will fair at longer range.
You can't necessarily attribute different points of impact to velocity differences when other things are in play. You even said it yourself, something along the lines of different loads come out of the barrel in different ways.
You can't necessarily attribute different points of impact to velocity differences when other things are in play. You even said it yourself, something along the lines of different loads come out of the barrel in different ways.
True, but I think the best explanation would be velocity change. As in, it was leaving the barrel sooner than other loads, and therefore happened to be leaving before the upswing(if you will excuse my crude term) of the barrel.
I believe it happens on the opposite side of the spectrum too though. As in, if you reached another velocity node that was on the same node as the other rounds your POI would be higher. But I'm next to positive its all on barrel timing.
What will be interesting to see is how it reacts at longer ranges. I'm sure people have done studies of this, but I have no clue how to search for something like that on the internet.
If you notice as I seated deeper the group center started to move back up. I wish I would have had good enough light to record the velocities on the Chrony as this was happening.
I'd load some more at the .020 jump with the 47 grain load and shoot a few groups to see if the accuracy is repeatable. If it is play with the powder charge and try to tighten it up.
I spent some time with the gun this weekend. I started by loading some more up with the 47 grains and .025" off. I liked how that group was centered more, and it was the same size as the other.
I was still shooting the same at 100 yards, so I stretched it on out to 200. It seemed alright I suppose. I still get these darn random fliers. But the bulk of the group seems tight. 3" group is "ok" for hunting at 200 yards.
First 5 shot group the 250 yard plate was around 5", strung horizontally, with one low. Again, not what I had hoped for, and I was scratching my head if it was me or the load. So I took a bit to think and decided to try a different load, to see if it would change things.
I upped the charge to 47.3 grains and shot a nice 7/8" group at 100 yards. No way of actually knowing if that was because of the load change, or just a better day shooting for me. But I tried it at 250 yards again. First three shots were 2 1/2", strung horizontally just about.
Then the next two opened it up, so I decided to load 4 more and see what a total of 9 shots produced. Yes, I am weird like that. I like to work in even numbers sometimes and that left me with 10 prepped cases to shoot. Anyways, the 9 shot group did open my eyes some.
6 of the 9 are clustered in a 3" group. One way left, and 2 way low. So honestly, I think that the outliers are my shooting skill not the load. Is that a pretty fair assessment? I can see where large group sizes are beneficial for seeing things like this.
I'm gonna call it good and work on my shooting skill now. One thing also is that these are factory second bullets. I went through them, weighed and measured them, they seem fine except some blemishes. But who knows how they are on the inside. Regardless, I am not going to say they were the cause. But next time, after some more practice, I'll repeat my test with some factory firsts.
I am not sure the velocity of the new 47.3 grain load. I'll run them over the chronograph soon. One thing that might be an issue was the cross winds I was dealing with. I try not to put blame on any one thing, but running some numbers it does seem that at 250 yards wind can play with POI. Next time I do a serious test I'll make sure its a calm day.
I realized I never have got a picture of the gun, so I decided to take one this weekend also. Nice little gun really. Definitely not a bench rest gun. I think half my issues is how light it is. Sure does like to jump when shot. But It will be perfect in the tree stand, walking around the woods, or packing in the mountains out west. I'll just have to limit my shots.
I'd not rule out the barrel making contact with the stock as the cause of the fliers.
As in during recoil it makes contact?
I know for sure it is floating up to the chamber just sitting there. It was one of the first things I did when I got the gun to make sure there was a very generous gap - not just a dollar bill sized one.
I honestly think its a combination of a few things. Trigger and rest being the biggest problem. The trigger is not horrible, but I do find it not breaking as easy as I would like it. My M700 is about the best trigger I have ever personally had. I'm gonna work on the Ruger's tonight.
I think the rest is the other culprit. I've been doing some reading, and it seems common place to hear of people having issues tightening groups with a solid "lead sled" type rest. Its superb for steady holding, which is why I got it - not because of recoil - but I think it does not allow it to recoil naturally.
I have tried to put it back into the holder the same after each shot, but who knows if something is a little different each time. I'm gonna break out the bags to do the rest of my testing.
I'd not rule out the barrel making contact with the stock as the cause of the fliers.
As in during recoil it makes contact?
I know for sure it is floating up to the chamber just sitting there. It was one of the first things I did when I got the gun to make sure there was a very generous gap - not just a dollar bill sized one.
Yes during recoil. I guess Ruger has stiffened the American stocks up some I haven't looked at the newer ones but the early ones were very flexible.
I suppose the stock could contact if enough force was applied, but it is pretty stiff. The solid rest I had it in for testing my have combined with it to cause the issues. I will say that if I were going to try and make this a target/bench gun I would do away with the synthetic stock very quickly. In fact, I have decided that I am going to get another RAR(full size) and use it as a base for adding stock and such too for target/bench type shooting. I think for a production gun they have a lot of potential.
I did work on the trigger yesterday. I started with removing the spring and putting a ball point pen spring in its place. It worked very well, but I could not get over the fact I put a pen spring in it so I dug through an old box of gun parts and found a good spring to use. The trigger pull is wonderful now. Very light(I have no scale), still safe, but allows you to be surprised. I thought about adding the "no creep" set screw in it, but for a hunting rifle this will do.
I put it on bags to shoot and was very pleased. I did find something very interesting which leads me to believe that most all of my fliers are caused by me. I started shooting at 150 yards and printed two right next to each other. However, I had to go reset my plate because it went crooked on the second shot. After shooting the third it fell off completely, and when I went back to look/put it on, the third shot was 1 1/2" left of the other two.
Then I shot the 250 yard plate. Fired three at it, and decided to go look. All in a nice group, 2 1/2" wide. Went back to shoot three more and they opened up the group with one wide left and one straight down. What this made me realize is that each time I got up, shifted my gun around, changed my seating and such is when the rest of the shots did not go into the main group.
I'm convinced that I have not found a solid anchor point yet, or a repeatable hold on the gun. I think that because it is such a light weight gun, and variance is causing the POI to shift. So its just a matter of working on this. I hope to shoot more tonight so I can put this into practice, but at this point I am convinced the load is great and I might should just move on to field shooting positions. It just one of those things that you want to have a target with a nice little group to show is all.
Well its a done deal I do believe. I got home yesterday and loaded up some rounds and setup on bags following the suggestions I read on this site light weight rifle shooting
I was blow away at the groups I got. Sub MOA all the way out to 250 yards. I still got the occasional flier, but I called each one. I knew if I was putting too much pressure, or squeezing off a round at the wrong time. The trigger on this thing is amazing and is something I am going to have to get used to all over again. I guess even though its not a real hard kicking caliber, the gun is light enough to cause inconsistencies that I have never seen in my other heavier guns.
Now it makes me wonder just how much I can tighten the groups, on other guns I have, by using proper shooting form. I am not a competition shooter, so I never cared that much about learning such stuff. Your hard pressed to use proper shooting form from a number of different hunting situations. But it does help to know these things when you go to testing loads, so you don't waste time and money.
I don't always shoot off the solid rest, I use bags and other field positions, but when I do use the rest I had always thought it was the best for testing accuracy. Now I understand the only real benefit to it is you don't have to deal with recoil on your shoulder. I am just not sure if that's worth more than the frustration of the negatives.
You are way over thinking things load some bullets and go shoot stuff
Guess you didn't read through it all, or you did and were confused?
I'm not over thinking things, just thinking through things out loud. Posting it all for future reference and for those who may be like me and run into some of the same things.
Just trying to be helpful. Anyone can just load bullets and "shoot stuff"........
