2nd outing with DPMS LR308

[J-ROD]

Overall it was a crappy range day...between the rain and crazy wind, I didn't get many chances to shoot. I put a new scope on this gun with a badger ordnance 22moa rail so it took me a few rounds to get it on at 100yds.
After the rain stopped, I painted and set up this target at 250yds which is as far as I can get at the farm.
This was the first group and really only group that I was able to squeeze off 5 rounds when the wind was down below 10mph and felt good about my form.
It measures right at 2" c2c (damn small cell phone pic, red squares are 1"x1"), Federal gold match 168gr. I don't know what to expect out of this gas gun but I do know that in all fairness, my shooting needs work.

I tried the 175grs and they grouped very poorly, the Hornady 155gr sst's did as well...I have no idea why.
For craps and grins I pulled the second 175gr round out of the gun after firing the first...and noticed two grooves rubbed into the bullet, looks as if they are coming from the corners of the "U" at the very top of the ramp leading into the chamber.
Should I smooth these down or let the gun do it gradually as I shoot (63rds thru it so far)?
I wanted to try a few rounds loading them individually but ran out of dry time. I did however manage to chrono a couple of the FGGM 168gr's -> avg 2634fps (24" barrel).

 

[Awesymoto]

Re: 2nd outing with DPMS LR308

at 250, your under 1 MOA which is good. My SASS likes the 175's did you check your twist rate? if its' over 1/10 then your rifle may prefer lighter loads like Hornady TAP 155.

 

[J-ROD]

Re: 2nd outing with DPMS LR308

Thanks for the response! I know it's 99% me, the gun can and has done better. I need to get a rear bag, work on trigger control and try again.
It should be 1/10, pardon the dumb question but is there a better way to check than looking down barrel and counting and doing the math? Maybe use a cleaning jag to count rotations?
I tried the Hornady ssts 155g and they were 6-7 in at 250. I'll get some TAP and try again

 

[2ndPanzer]

Re: 2nd outing with DPMS LR308

Sure, the cleaning rod method is easy. Get it started, make a mark, and another further up on the same side as your close in mark, then push it until you observe one rotation, then make another mark using the same reference point you made the first one. Measure the distance and you'll be there.

Less than 1moa is good shooting on an AR type rifle. They are pretty unforgiving to the shooter and getting consistent results is challenging. You did good. I'd try some 175's and see how they do. 155's are a little trickier in some rifles to get to shoot good. But when they do, they usually do very well. With that 24 in barrel you can push them pretty good. They seem to like being pushed hard.

 

[J-ROD]

Re: 2nd outing with DPMS LR308

Thanks again for the responses, compliments and tips.
I was shooting off of a bipod in the front and a balled up jacket in the rear. I just made a DIY rear bag with a sock and some rice...some dry firing trials proved to be much more stable than before but I won't know for sure until Friday evening when I go again.
I hated to do it but I also moved my scope back. Where it was, my cheek was half off/on the end of the cheek riser and I just couldn't stay comfortable & consistent. Now my cheek is completely on the cheek riser and the gun feels much mo betta.

On another note, just to muddy the water. I have a friend who offered me fair money for the DPMS w/o scope & rings..so I was looking at a savage fvss with B&C medalist stock, I don't want to start a bolt vs semi war but I am wondering if this 1moa shooter would be better off with an easier to shoot 1/2moa gun...hmm...decisions decisions

 

[J.Boyette]

Re: 2nd outing with DPMS LR308

RICE ETR,

2 questions before I get started to help out.

1. Does your upper have a dust cover and forward assist?

2. Did you shoot the last round and have a bolt lock back each time?

Thanks

 

[J-ROD]

Re: 2nd outing with DPMS LR308

Dang, well I just happened to read the CLP in bore thread in the bolt section, I have been doing that. Ok, i've obviously got a lot to learn.
Man this forum is great...priceless info.

 

[J-ROD]

Re: 2nd outing with DPMS LR308

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: J.Boyette</div><div class="ubbcode-body">RICE ETR,

2 questions before I get started to help out.

1. Does your upper have a dust cover and forward assist?

2. Did you shoot the last round and have a bolt lock back each time?

Thanks </div></div>

1.) No dust cover or forward assist.

2.) Yes; I would load 5 rounds, shoot 5 rounds, let the barrel cool. The bolt locked back each time. fwiw the gun also cycles flawlessly. I just purchased a Magpul polymer mag as I noticed some shavings on the 90 degree tang on the front of stock steel mags, upon closer inspection, the ogive drags on it as the rounds are being loaded.

Thanks in advance for your time and help.

 

[J.Boyette]

Re: 2nd outing with DPMS LR308

Ok,

That upper is the smooth side upper. Its a tall rail on top. So that Bad Ord 22 MOA rail will bring the optic up REAL high. I can not tell, but if you have a PRS stock on it, you got to adjust the cheek piece up ALOT. If you have a A2 stock on it you are using s chin weld, not a cheek weld.

Something to think about.

On the PRS, if you have one, and using the cheek weld you will short stock the rifle, this will make your body be at a angle when shooting prone. This can in turn push rounds to the other side you shoot on.

Somethings to things about.

Next,

Load 6 rounds and shoot 5 or load a snap cap first then load 5 rounds. Run the rifle as a closed bolt system and see if the flyers drop down ALOT. With the bolt locking to the rear on the last shot you get a different recoil then a closed bolt every time.

You did good at 250yds. Running a gas gun above .223 is not a easy task. Keep working at it and you will be a better marksman.

enjoy.

John

 

[Casey Simpson]

Re: 2nd outing with DPMS LR308


Rice eter, that barrel is stamped on the bottom side with the twist rate if it is the barrel it appears to be.

Those sharp edges on the feed ramp probably don't hurt much but I don't like 'em either and remove em. At times feedramps can be bad enough to upset the overall length of the round. Bad! And some of this can be remedied by tuning the mag lips to pois the round bullet slightly higher than the case rim. Check it out.

Ignore the wind. Just means you'll have horizontal dispersion in the points of impact. Your concerned with vertical dispersion. Account for it and keep shooting.

Grease your carrier rails, locking lugs, sear and hammer surfaces and hold on to that big chassis AR. You'll be fine with it after a coupla hundred rounds.

 

[J-ROD]

Re: 2nd outing with DPMS LR308

John, here is a pic of my current optic set-up and yea there's a prs stock on it too....

The LoP is as far as I can get it but the cheek weld is only up maybe 3/4 of a turn, but as I said it's comfortable. Based off the pic, would you say my form would have to be screwed up with a scope that high? I guess I don't "need" the 22moa rail if it will help my shooting...kind of a moot point at the yardages I would need it anyways.
I will for sure try the 6 round, 5 shot group tip, thanks.

Casey, yea the underside says 1-10 so that makes me feel good about my counting to 1 skills...lol. Kinda sad that I've never looked there...duh.
Ahhh, ok, makes complete sense, again duh... I will do that as well Friday, just focus on getting good shots off and record vertical bullet "grouping".
I've been using CLP but have always wondered if things would benefit from a little more load bearing lubricant. I have marine grease in a tube, that ok or should I just get normal lithium?
Since I have both of the original steel mags as spares, I can afford to bend one up a little.

I can't thank you guys enough for spoon feeding me along!

-Jarrod

 

[jkillebrew]

Re: 2nd outing with DPMS LR308

I just got my scope (vortex viper pst) in today for my new DPMS LR308 and will be getting rings ordered tomorrow to hopefully start shooting it next week! This thread is awesome and hopefully I can follow your questions to find answers of my own!

 

[J-ROD]

Re: 2nd outing with DPMS LR308

You are going to love your DPMS, it really is a lot of fun to shoot and way more accurate than I am. I am looking forward to shooting tomorrow after all the help from this thread and pm's. The guys on this forum are great!
Definitely post up pics and results once you get yours together, goodluck!!

 

[J-ROD]

Re: 2nd outing with DPMS LR308

Well first off I have to give thanks to all the people who helped me in this thread and via pm's, Casey you are the man!!

I left work later than I wanted and it's about an hour drive to the farm where I can shoot. My brother brought his mosin nagant out there with a scope kit on it so we spent a good amount of time getting that straight with the Burris Signature Zee rings (needed +.020 in the rear and -.010 in front just to get it on at 100...wow)
Anywho, I started with a clean and oil free barrel, fired off 5 rounds at a time trying different ammo at 100yds.
Groups were decent, ~1moa or better with most of what I tried. the Fiocchi were horrible! Around 2"-3" groups at 100yds. Hornady 155sst's still horrible as well.
Although I couldn't really get comfortable behind the gun off the ground, below is a typical 100yd group with my favorite ammo with this gun, fgmm 168grs:

We drove my Yota back to the same 250yds as before, and shot off the top of it...I'm a little more comfortable there oddly enough (bipod in front, DIY rice bag in rear). I shot 5 rounds of my old faithful 168gr fgmm, let the barrel cool while my brother shot his mosin, then I shot 5 with 175gr smk fgmm. I knew the 168 group was either really good or really bad through my scope as I didn't see any hits. The 175gr group I knew was bad. I am sure some will think I am full of it but I don't care, I was there as well as two witnesses....my brother and the Big Man upstairs

The first pic below is my 250yd group with the 168's...it took me an honest 5 mins to shoot these five shots as I was trying to get settled in behind the gun. That's a nickel btw and a ~1" square. From 100yd zero, exactly 2moa up on the turrets is 250yds with my gun, scope height of 2.75in c2c.

Next is the 175gr group....my gun just does not like the 175's, which is a bummer because I will need them if I go big.

I was stoked but had a hot barrel so in the mean time decided I would work on my bro's gun to get it to group less than 10" at 250yds. It started out with a few patches and a few minutes then ended up being about an hour trying to get the copper fouling out (I'm pretty sure it had never been cleaned, ever!).
I wanted to shoot some more groups but I couldn't really see the red squares..."of course" is what I'm sure most of you are thinking I know. I don't doubt that group was a complete freak accident, never to be repeated again but either way it left me with a smile on my face all the way home and I owe you guys for freely giving me all of your hard earned info/tips.

Now with all that said, I am going to say something absolutely idiotic and complain some more. I am still thinking I may sell this gun to my friend...I honestly just can not get comfortable with it (have to run the 9-13" bipod due to mag so the gun is up high, the pistol grip used to suit me well, now not so much, the gun is hard on brass...blah blah blah) and I really wish it would shoot some type of 175smk well. Maybe it's just me and my poor form showing up more with the slightly added recoil, I don't know. If I decide to do what I should do, put some more rounds through it and get better (see if I can get anywhere close to the magic group above) then I would like to trade someone 180rounds of fgmm 175gr for some fgmm 168gr ammo if anyone is interested.

One thing I did learn is that of the 35ish rounds I shot today, my last round was never a flier...if I had one it was round 2 or 3....so I have no idea on that.

I am really thinking of a remmy 700 sps varmint or the like in 308. I don't know, I think it's just late and I'm going crazy. But I am much more comforable with my marlin than my DPMS

FWIW below is one of my marlin .17hmr's groups at 100yds...my little bedding experiment with Devcon (again thanks to this forum) paid off big time. The gun used to be 1 to 1.5moa at 100yds, now it's excellent minus the one flier where I was excited about the 4 previous rounds and wanted to hurry up and see my group. Disregard the two random mosin rounds.

 

[PowerstrokeOBX]

Re: 2nd outing with DPMS LR308

I'd take those groups any day from a 900$ semi. Some people pay near 5k and can't get good groups like that.

Maybe you should stick to a bolt?

But if you can't get comfy I then I don't blame you.

 

[J-ROD]

Re: 2nd outing with DPMS LR308

Thanks, and yes I know, it's very ignorant and silly for me to be complaining. The gun flat out shoots. I may try a 6-9" bipod and see how low I can go with it and still have the mag clear. I don't know where my elbows are supposed to be while in the prone position but they are at a pretty steep angle trying to get up on the cheek weld.

I found out a little bit ago that the dang scope MOA scale rings for the turrets on my Nikon Buckmaster are loose, both the windage and elevation...so I am not sure about the 2MOA up at 250yds. I don't know if I need to send it back or just glue them in place. Kind of makes me lose a lot of confidence in the scope.

 

[colodog]

Re: 2nd outing with DPMS LR308

Man I wish I had your problems

I have a $3K POF with a Mark 4 on it that won't shot that group @100 yds. I say Keep the rifle.