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Posted: 7/7/2018 1:57:54 PM EDT
MAde it out to the "long" range today first time with my new 18 inch 223 wylde Green mountain barrel. I had previously zeroed and chronoed the rifle at 100 yards using Magtech 5.56 77gr otm (mk262 clone) I went through a 50 rounds box and averaged 2743 fps with the chrono 10 feet in front of the rifle. Im in central florida so elevation is almost 0 but temp was 75* and 80% humidity when I zeroed. Today on the "500" yard line which turns out is really 475 that really through me off the first time I went out there... It was 85* 100% humidity very little wind maybe 2mph at most.

I am using strelok pro and have all of my info entered such as scope height (2.75in) bullet data ect

I started at 200 and worked out to 400 yards with calculator and everything was dead on. Once I switched to the 475 yard target (they call it 500 but it isnt really) Strelok said dial up 10moa. The targets are full size IPSC silhouette steel targets and holding center mass with a 1moa hold for wind at the target I was hitting high. I backed down my elevation in increments until I was hitting POA which ended up at 9 moa. My Scope is a Bushnell Enage 2.5-10 in MOA and it tracks true

What would explain that difference in elevation? Is it just the calculator gets you close and actual impacts can vary? Or am I doing something wrong?

I am new to the long range shooting and trying to do and learn as much as I can with the 223 before investing in a larger caliber to go further out
Link Posted: 7/7/2018 2:17:05 PM EDT
Link Posted: 7/7/2018 2:32:42 PM EDT
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Originally Posted By Rob01:
Ballistic calculators aren't always on 100% of the time. They get you close. Same ammo lot number? Did you recheck your zero? The temp difference might have done it if you were still using 75 degree data but if you changed it to 85 then it wasn't that. The humidity won't effect anything at those ranges. Just make sure everything is right in your program inputs. Once you start going out farther even little mistakes will start showing up.

Log that data and next time out you just dial it in and make a hit. Actual data always trumps programs.
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Yeah ammo is all from the same lot. I had bought 500 rounds last time and all the boxes match. I did not recheck the zero at 100 this time though the last 3 times I went to the range and shot 100 yards I used the same ammo with the same zero and nothing had changed.

So at this point I should make log book/dope sheet the calculator works fine out to 400 past that I need to put rounds on target and log it and build from there
Link Posted: 7/7/2018 11:36:25 PM EDT
Calculations are just a guide. My experience has been the same as yours... calculations called for more than what was actually needed.

Like mentioned above, best data is your live-fire data, then confirm at a later date under the same conditions.
Link Posted: 7/8/2018 2:25:41 PM EDT
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Originally Posted By Bowhntr6pt:
Calculations are just a guide. My experience has been the same as yours... calculations called for more than what was actually needed.

Like mentioned above, best data is your live-fire data, then confirm at a later date under the same conditions.
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Exactly this.

Calculators are just to get you in the ballpark; you need to actually shoot at known distance and record your come-ups. Then rinse/repeat a few times until you've got an established pattern.

It can be frustrating as ammo lots (if you're shooting factory), and environmental conditions make quite an impact.

Hence why it can be so difficult to get "first round hits" at extended ranges.
Link Posted: 7/8/2018 5:33:40 PM EDT
I wrote down my adjustments so next time I go I know where to dial and will see what happens
Link Posted: 7/9/2018 8:30:57 AM EDT
[Last Edit: 7/9/2018 8:31:27 AM EDT by Evile]
So I started doing more research and came across this video on truing muzzle velocity which described exactly what I experienced. So I found in Strelok pro the option to do this, Entered my rage to target and how many clicks it took to be on target hit compute and get a muzzle velocity of 2893 fps which is much higher than my previously chronoed 2743 fps.

So Ill take this info and apply it to my next trip to the range. Hopefully the owner is there this time and he will qualify me for the 1000 yard range and I can push the 556 out as far as i can

Link Posted: 7/9/2018 8:50:28 AM EDT
[Last Edit: 7/9/2018 8:57:26 AM EDT by popnfresh]
I"ll go against the grain here, IME ballistic calcs are very accurate. They should get you with in a 0.1mil or two out to 1k yds providing there are no odd drafts.

Garbage in garbage out is the saying. Most who have issues are using sloppy inputs.

So did you do a tracking test and input the tracking error into the calc?

Did you input your exact zero offsets on this day?

Did you get velocity data at the time of shooting?

Did you input all atmospheric data collected from your Kestrel?

No to any of those and a few more obvious ones and you will have problems.
Link Posted: 7/9/2018 9:11:56 AM EDT
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Originally Posted By popnfresh:
I"ll go against the grain here, IME ballistic calcs are very accurate. They should get you with in a 0.1mil or two out to 1k yds providing there are no odd drafts.

Garbage in garbage out is the saying. Most who have issues are using sloppy inputs.

So did you do a tracking test and input the tracking error into the calc?

Did you input your exact zero offsets on this day?

Did you get velocity data at the time of shooting?

Did you input all atmospheric data collected from your Kestrel?

No to any of those and a few more obvious ones and you will have problems.
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I did a tracking box test when I first got the scope and it tracked true, each adjustment impacted where it was supposed to.

No to the next two items. I didn't check my zero before I started shooting. I had confirmed my zero the last 3 trips and my turrets lock and had not moved. And I did not bring my chronograph this trip.

I don't have a kestrel but I did get temp humidity and wind from a different device.
Link Posted: 7/9/2018 12:21:07 PM EDT
[Last Edit: 7/9/2018 12:29:24 PM EDT by popnfresh]
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Originally Posted By Evile:

I did a tracking box test when I first got the scope and it tracked true, each adjustment impacted where it was supposed to.

No to the next two items. I didn't check my zero before I started shooting. I had confirmed my zero the last 3 trips and my turrets lock and had not moved. And I did not bring my chronograph this trip.

I don't have a kestrel but I did get temp humidity and wind from a different device.
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If you input all the data precisely you can expect better results.

Before doing any calibration to the app I would first try it with all the correct info that you can gather.

So with no Kestrel you could input air temp, 50% humidity, and 29.92 in/hg(assuming Florida).

Measure MV just before shooting and use that number. Keep your ammo out of the sun and away from hot things(keep it ambient temp).

Fire a group and measure zero offsets and put those into the calc. You don't need to re-zero the scope.
If you are 1.125" high of aim point at 100yds, just put that into your zero info. +1.125.

Then of course distance to target should be accurate as possible.

If you true the app for only one distance or a short distance then it may correct the wrong variable and be off at every other distance past the truing distance.

Here is where the zero offset is.
Attachment Attached File
Link Posted: 7/9/2018 12:43:49 PM EDT
Sounds to me like you have a slight BC correction on the bullet plus a switch in wind such as a tail wind. With high humidity sometimes you get a little higher lift of the bullet. I think Strelock pro uses Density altitude which sometimes doesn't account for over 80% humidity. But that's why a log book is so important that way the next range visit you can recheck your actual shooting data to the apt data.
Link Posted: 7/9/2018 12:51:27 PM EDT
It's summer time in Florida which means 90*+ Temps and 80%+ humidity

I had zerod the rifle a month ago in the morning when it was 75 but still high humidity.

Would that temp difference cause the shift in poi?

When I go back next time I'll check my zero at 100 and see if it's moved and input the offset if it has changed.
Link Posted: 7/9/2018 1:39:39 PM EDT
[Last Edit: 7/9/2018 1:40:57 PM EDT by popnfresh]
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By Evile:
It's summer time in Florida which means 90*+ Temps and 80%+ humidity

I had zerod the rifle a month ago in the morning when it was 75 but still high humidity.

Would that temp difference cause the shift in poi?

When I go back next time I'll check my zero at 100 and see if it's moved and input the offset if it has changed.
View Quote
Humidity has very little effect, it would be the least of your problems, leaving it at 50 or 60 or 70% would be fine since you don't have a Kestrel.

Your ammo temp difference can cause a big change in velocity.

A different MV can change poi from your zero.
Link Posted: 7/9/2018 1:48:42 PM EDT
[Last Edit: 7/9/2018 1:49:19 PM EDT by Evile]
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Originally Posted By popnfresh:

Humidity has very little effect, it would be the least of your problems, leaving it at 50 or 60 or 70% would be fine since you don't have a Kestrel.

Your ammo temp difference can cause a big change in velocity.

A different MV can change poi from your zero.
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So this is where the logbook comes in right? Write this sessions results down next time I go out do the same rinse and repeat?

Other than checking mv each time I go with the chrono

Anyone got a link to a good logbook or spreadsheet to track this and keep it organized?
Link Posted: 7/9/2018 2:06:40 PM EDT
[Last Edit: 7/9/2018 2:08:02 PM EDT by popnfresh]
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Originally Posted By Evile:

So this is where the logbook comes in right? Write this sessions results down next time I go out do the same rinse and repeat?

Other than checking mv each time I go with the chrono

Anyone got a link to a good logbook or spreadsheet to track this and keep it organized?
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Yes, if you are ever without your gizmos a good log book and/or range cards are all you have .

I just use those little 3"x5" notebooks, one for each rifle.

Everytime out I write down ammo temp, air temp, wind, pressure, humidity, DA, MV data, # of rounds fired, # of rounds since cleaned, and load details.

If I am shooting long range I get all the above plus predicted drop from calc and actual drop at each distance.
Link Posted: 7/11/2018 10:26:08 PM EDT
Quite honestly, OP, I think a few more details would help. Let's start with your brand new barrel. What is the twist in it? Do you know if it is an accurate barrel, ergo, have you shot quality ammo through it and produced any sub-minute groups?

My assessment is a simple one. I'm going to say much of your issue is your ammo. I speak from experience when I say Magtech makes straight shit ammo. I know you ran the ammo over a chrono, how many rounds did you run and what were your SD and ES valuations?

Obviously, when your targets are closer in, variances in your ammo's velocity are negligible. However, as you start to stretch legs (which 500 yards certainly is with .223). What may be a relatively minor variance at 300 becomes much more amplified at 500.

My experience is anecdotal, so I did find this article for you, which was actually a great read. Specifically, it stated, the CBC (which is Magtech), "had one of the higher standard deviations of all ammo tested."

Not knowing the details with regards to your barrel, and again, from all of my personal experience, I'd recommend you go grab a quality 69gr load, such as some Federal Gold Medal Match or Black Hills 69gr and run it.

IMHO the CBC 77gr you're shooting is just a bit better than, say, some Wolf or Fiocchi, but not on the same playing field as FGMM or BH. I believe it is great ammo for plinking and what not, but I would not rely on it for precision or any kind of accuracy testing on your rifle.

Good luck. Keep us posted.
Link Posted: 7/11/2018 10:47:14 PM EDT
[Last Edit: 7/12/2018 8:10:38 AM EDT by Evile]
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By FALex:
Quite honestly, OP, I think a few more details would help. Let's start with your brand new barrel. What is the twist in it? Do you know if it is an accurate barrel, ergo, have you shot quality ammo through it and produced any sub-minute groups?

My assessment is a simple one. I'm going to say much of your issue is your ammo. I speak from experience when I say Magtech makes straight shit ammo. I know you ran the ammo over a chrono, how many rounds did you run and what were your SD and ES valuations?

Obviously, when your targets are closer in, variances in your ammo's velocity are negligible. However, as you start to stretch legs (which 500 yards certainly is with .223). What may be a relatively minor variance at 300 becomes much more amplified at 500.

My experience is anecdotal, so I did find this article for you, which was actually a great read. Specifically, it stated, the CBC (which is Magtech), "had one of the higher standard deviations of all ammo tested."

Not knowing the details with regards to your barrel, and again, from all of my personal experience, I'd recommend you go grab a quality 69gr load, such as some Federal Gold Medal Match or Black Hills 69gr and run it.

IMHO the CBC 77gr you're shooting is just a bit better than, say, some Wolf or Fiocchi, but not on the same playing field as FGMM or BH. I believe it is great ammo for plinking and what not, but I would not rely on it for precision or any kind of accuracy testing on your rifle.

Good luck. Keep us posted.
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The barrel is a green mountain 18inch 223 Wylde 416r ss fluted barrel 1/8twist. I've put several types of match ammo nosler and gorilla 69gr have produced the best groups all sub moa. The magtech 77gr stuff is consistently moa or better. I shot full box of 50 over the chrono, I'd have to back and check the SD on them.

Edit.. The Caldwell app does not doesn't work with my LG phone so I use an older s4 with it so I don't have every chrono result saved but here is one batch of 10 shots.

Created: 06-07-2018 07:38:46 AM
Description: magtech 5.56 spr
Notes 1: magtech 5.56 HPBT MatchK 77.00 0
Notes 2:
Distance to Chrono (FT): 0.00
Ballistic Coefficient: 0.367
Bullet Weight (gr): 77.000
Altitude (FT): 0.0
Temp: N/A
BP: N/A
Shots
#

FPS

FT-LBS

PF
10 2736

1280.08 210.67

9

2799

1339.71 215.52

8

2744

1287.58 211.29

7

2726

1270.74 209.90

6

2729

1273.54 210.13

5

2761

1303.58 212.60

4

2730

1274.48 210.21

3

2759

1301.70 212.44

2

2750

1293.22 211.75

1

2748

1291.34 211.60

Average: 2748.20
StdDev: 21.66
Min: 2726
Max: 2799
Spread: 73
True MV: 2748.20
Shots/sec: 0.37
Group Size (IN): 0.00
Link Posted: 7/22/2018 1:12:07 PM EDT
Update after today's range session.

Chronoed my rounds this time. Same lot number magtech 5.56 77gr otm, 2746 was the average of 10 rounds. zero was dead on no off set difference temp a d humidity was the same as last time hot as balls 90 with 90% humidity wind was all over the place. From the bench sometimes it was from behind others was the left and after talking to some guys at the range they say it sometimes swirls at the target.

Using last trips info I dialed to 9moa again instead of the called for 10moa for 475 yards and once I figured out the wind with holds I was on target. It took 1.5moa left to account for wind.

A fellow shooter with a 6-24 scope was spotting for me and said I was hitting center mass every time.

So I wrote all this down and am keeping track now
Link Posted: 7/22/2018 7:15:23 PM EDT
[Last Edit: 7/22/2018 7:18:36 PM EDT by Mister_H]
OP, a strange and often overlooked phenomenon that can effect your actual elevation vs calculated elevation is aerodynamic jump.

I blame Bryan Litz.

It could be a parallax issue or inconsistent scope mechanical tracking too.
Link Posted: 7/23/2018 9:06:01 AM EDT
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Originally Posted By Mister_H:
OP, a strange and often overlooked phenomenon that can effect your actual elevation vs calculated elevation is aerodynamic jump.

I blame Bryan Litz.
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Don't blame him because at that range it is only an inch difference, less than one click on OPs scope.
Link Posted: 7/24/2018 8:49:27 AM EDT
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By popnfresh:
Don't blame him because at that range it is only an inch difference, less than one click on OPs scope.
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Originally Posted By popnfresh:
Originally Posted By Mister_H:
OP, a strange and often overlooked phenomenon that can effect your actual elevation vs calculated elevation is aerodynamic jump.

I blame Bryan Litz.
Don't blame him because at that range it is only an inch difference, less than one click on OPs scope.
I was just suggesting it could be a contributing factor, not the sole factor.
Link Posted: 7/24/2018 2:48:32 PM EDT
[Last Edit: 7/25/2018 9:13:01 AM EDT by Reorx]
Food for thought >>> At that range, 25 yards plus or minus will effect the POI about 1 moa (up or down)... How confident are you that the range you have input is correct??? I know it sounds crazy that it might be off by that much but when the folks at the range call 475 yards, 500 yards, it makes me wonder... Next time you are out there, consider actually measuring the distance!...

Edit: Just re-read your post(s)... everything is "dead on" @ 100, 200, & 400 yards and then off by an entire MOA at 475! Go to the range and (assuming they are in line) stand next to the 400 yard target and laser range the "475 yard" target... let me know what you find! The "fact pattern" sounds like the 475 yard target is actually at 450 yards!
Link Posted: 7/24/2018 4:20:51 PM EDT
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By Reorx:
Food for thought >>> At that range, 25 yards plus or minus will effect the POI about 1 moa (up or down)... How confident are you that the range you have input is correct??? I know it sounds crazy that it might be off by that much but when the folks at the range call 457 yards, 500 yards, it makes me wonder... Next time you are out there, consider actually measuring the distance!...

Edit: Just re-read your post(s)... everything is "dead on" @ 100, 200, & 400 yards and then off by an entire MOA at 475! Go to the range and (assuming they are in line) stand next to the 400 yard target and laser range the "475 yard" target... let me know what you find! The "fact pattern" sounds like the 475 yard target is actually at 450 yards!
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Problem is how the range is setup they don't allow anyone past the 100 yard berm and I don't have a range finder yet. It's on my wish list. Here is a screen shot using a app to measure distance on Google earth Attachment Attached File
Link Posted: 7/24/2018 5:36:06 PM EDT
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Originally Posted By popnfresh:
I"ll go against the grain here, IME ballistic calcs are very accurate. They should get you with in a 0.1mil or two out to 1k yds providing there are no odd drafts.

Garbage in garbage out is the saying. Most who have issues are using sloppy inputs.

So did you do a tracking test and input the tracking error into the calc?

Did you input your exact zero offsets on this day?

Did you get velocity data at the time of shooting?

Did you input all atmospheric data collected from your Kestrel?

No to any of those and a few more obvious ones and you will have problems.
View Quote
Roger that. Ballistics calculators plus a Kestrel has changed long range shooting.

At my last course, I entered in one of the attendee's BC into Strelok (free), entered in temp and barometric pressure from Kestrel, and I'll be a danged if he (new shooter, no LR experience) doesn't center-punch everything from 200-1000yds. Everything was literally, textbook center-punch like I have rarely seen (been doing this since 1995).

He was using a Ruger RPR 6.5 Creedmoor, Vortex Razor HD, in a high quality mount with a bubble level though. 130gr Prime ammo, which is fantastic.

A Kestrel is scary game-changing if you know how to use your equipment, and that's not even the blue-toothed options you have nowadays with LRF-linked to Blue Tooth and Kestrel.
Link Posted: 7/24/2018 7:05:59 PM EDT
[Last Edit: 7/24/2018 7:09:49 PM EDT by Reorx]
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By Evile:

Problem is how the range is setup they don't allow anyone past the 100 yard berm and I don't have a range finder yet. It's on my wish list. Here is a screen shot using a app to measure distance on Google earth https://www.AR15.Com/media/mediaFiles/239042/Screenshot_20180724-161721-618105.JPG
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OK, so I looked using my laptop with Google Earth. I think target placement is at least part of the problem. I measured the 400 yard berm and it is essentially exactly 400 yards from the firing line. 75 yards behind the 400 yard berm is definitely behind the last berm on that range. A target in front of that berm could easily be closer to 450 yards than 475 so I think that this is at least part of the problem and it could indeed be the whole problem if they are sloppy with target placement at that last berm!... The ends of my ruler in the image below were placed where the slope of the berm meets the flat earth in front of it - as best as I could tell...



See if you can get a closer look... & let us know...

Best!

- R -

P.S.: I didn't know that you were just up the road from me... I'm in Palm Beach County!!! Howdy neighbor!
Link Posted: 7/24/2018 7:54:46 PM EDT
[Last Edit: 7/24/2018 8:02:11 PM EDT by Evile]
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By Reorx:
OK, so I looked using my laptop with Google Earth. I think target placement is at least part of the problem. I measured the 400 yard berm and it is essentially exactly 400 yards from the firing line. 75 yards behind the 400 yard berm is definitely behind the last berm on that range. A target in front of that berm could easily be closer to 450 yards than 475 so I think that this is at least part of the problem and it could indeed be the whole problem if they are sloppy with target placement at that last berm!... The ends of my ruler in the image below were placed where the slope of the berm meets the flat earth in front of it - as best as I could tell...

https://i.imgur.com/7bpFowv.png

See if you can get a closer look... & let us know...

Best!

- R -

P.S.: I didn't know that you were just up the road from me... I'm in Palm Beach County!!! Howdy neighbor!
View Quote
seems like i really need that laser range finder to get an exact measurement

plugging in 450 yards gets me to where my actual impacts are at 9moa, If they are are putting the target all the way against the berm it might be 470 but depends how far they bring it forward I guess. You know how much rain we have been getting and the place is super swampy right now so maybe they brought in in closer out of a mud puddle
Link Posted: 7/24/2018 8:08:24 PM EDT
[Last Edit: 7/24/2018 9:04:18 PM EDT by Reorx]
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By Evile:
...If they are are putting the target all the way against the berm it might be 470 but depends how far they bring it forward I guess. You know how much rain we have been getting and the place is super swampy right now so maybe they brought it in closer out of a mud puddle
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...my thoughts exactly!!!

When it rains a lot (summer), the target area at the range that I usually shoot at gets pretty swampy... it gets difficult to get to the target stands without a good pair of waterproof boots. But there is only one place to put targets so the distances are always within a yard or 2 of the stated distance (100, 200 or 300 yards).
Link Posted: 7/24/2018 8:21:31 PM EDT
I always enjoy when a technical thread gets technical and we actually work stuff out and learn something lol

for now Until I can get a rangefinder Ill keep shooting and recording what adjustments Im making
Link Posted: 7/24/2018 8:34:02 PM EDT
[Last Edit: 7/24/2018 9:14:27 PM EDT by Reorx]
Discussion ForumsJump to Quoted PostQuote History
Originally Posted By Evile:
...Until I can get a rangefinder Ill keep shooting and recording what adjustments Im making
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Good idea! Next time you are out there shooting, you can ask up and down the line - there is a fair chance that one of the other shooters will have a rangefinder you can borrow for a second or 2... I carry a range finder, binoculars, etc. in either my rifle case or my range bag... maybe one of your cohorts in Leesberg does as well!!
Link Posted: 9/9/2018 2:20:49 PM EDT
So a bit of an update to this post!

I bought a range finder a Laserwork 1000 and it works great. I compared it to a co workers leupold and the measured identical.

Went out to the range today set up and checked the 500 yard target and it was ranging 480 yards from the bench to the target. Strelok again told me 10moa up and I was hitting but it was high. 9 moa put it right in the middle. and there was zero wind this morning.

I did qualify for the long range which is 6-900 yards today also so I went out there with another shooter who had a ruger precision rifle in 6.5c and I was able to easily connect at 600 and 75% of shots at 700 yards. with Strelok being dead on for both of those

One thing I learned today was I don't need a huge amount of zoom to shoot long range. I compared my $300 Bushnell engage 2.5-10 to the other guys Nightfroce 5-20x $1300 scope and I couldn't tell a $900 difference in terms of glass clarity even he admitted the Engage had awesome glass for the price point. Granted his had zero stop more travel and other things but clarity and brightness I couldn't tell.

The next rifle I build will either be 6.5g or 224 so I can hit the 900 yard line but the 556 has made for an excellent learning platform.
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