Scope for 50 BMG & 338 Lapua

Optics Discussions

Moderators: Barrett Optics, Moose99, Barrett Forum, Samurai, Barrett

User avatar
ersc
Active Poster
Posts: 68
Joined: Mon 20 Apr, 2009 4:20 pm
NRA Member: yes
Military: yes
Location: Minnestoa

Scope for 50 BMG & 338 Lapua

Postby ersc » Sun 27 Feb, 2011 1:49 pm

Hi Folks

I am getting a 338 Lapua and need to get a scope for it... I am going with Night Force and am down to two selections...

12-42x56 Benchrest http://nightforceoptics.com/nightforcescopes/SCOPES_OVERVIEW/BENCHREST_MODELS/benchrest_models.html
or
12-42x56 NXS http://nightforceoptics.com/nightforcescopes/SCOPES_OVERVIEW/8-32x56___12-42x56/8-32x56___12-42x56.html

Opinions between the two scopes? (don't plan to drag through the wood and drop off cliff, looking for accuracy)



Opinions: between rfiles and scopes? (these two rifles have an easy life)

I currently have a Burris XTR 6X-24X-50mm on my 32" Barrett 99...

Given that I will have these two scope, which configurations would be optimal?

M99 with Burris XTR 6X-24X-50 338 and 338 Lapua with Nightforce 12-42x56?
or
M99 with Nightforce 12-42x56 and 338 Lapua with Burris XTR 6X-24X-50?

Thanks
[ 50 BMG Cooridnator for my loccal sportsman's club -- Retired Navy ] Men trained in arms from their infancy, and animated by the love of liberty, will afford neither a cheap or easy conquest. Declaration of the Continental Congress, July 1775
Ludington1
Newbie
Posts: 20
Joined: Tue 27 Jul, 2010 2:03 pm
Carry Permit: yes
Favorite Firearm: Barrett M99-A1

Re: Scope for 50 BMG & 338 Lapua

Postby Ludington1 » Sun 27 Feb, 2011 11:01 pm

I'm pretty new around here, but one thing I have learned by reading lots of opinions on this site is that those are probably way too much magnification for real-world use. Other than that, I'll leave it to the pros to add their opinions.

Darren
User avatar
flyjets
Member
Posts: 245
Joined: Mon 20 Apr, 2009 12:21 pm
NRA Member: yes
Military: yes
Carry Permit: yes
Favorite Firearm: 1874 Sharps
Favorite Ammo: Lapua

Re: Scope for 50 BMG & 338 Lapua

Postby flyjets » Mon 28 Feb, 2011 9:23 pm

Hi ERSC

Been a while I trust your doing well.

I would not recommend the BR scope for either rifle. The focus adjustment is not as user friendly located on the objective lens. It is also a bit stiffer then the side focus.
The clicks are 1/8 MOA needed on a Benchrest Rifle not necessary on the M99 or M98 or any production Barrett. The Adjustments knobs are smaller and not as legible.

Also the 12 * 42 even with a 40 min MOA internal adjustment this would limit the range to 1150 yards.

The 8 * 32 gets you 1300 yards.

Since I have been using the 12 * 42 BR the 8 * 32 NXS & the 5.5 *22 NXS Zero stop. I would recommend the 8 * 32 or the 5.5 * 22 NXS models.

If you like more magnification the 8 * 32 works well but to be honest I seldom run it beyond 22 times.

NPR1 recticle is a nice addition.
http://nightforceoptics.com/nightforces ... rview.html

If I can answer anything more detailed question just E mail me.

Ian
Management is doing things right; leadership is doing the right things.
User avatar
ersc
Active Poster
Posts: 68
Joined: Mon 20 Apr, 2009 4:20 pm
NRA Member: yes
Military: yes
Location: Minnestoa

Re: Scope for 50 BMG & 338 Lapua

Postby ersc » Mon 28 Feb, 2011 9:36 pm

Hi flyjets

Great feedback, Thanks...

If you have a 20 or 27 MOA rail does that mean you can add 20 MOA to the 40 MOA (limit of the scope) and have a total of 60 MOA of elevation?
[ 50 BMG Cooridnator for my loccal sportsman's club -- Retired Navy ] Men trained in arms from their infancy, and animated by the love of liberty, will afford neither a cheap or easy conquest. Declaration of the Continental Congress, July 1775
User avatar
flyjets
Member
Posts: 245
Joined: Mon 20 Apr, 2009 12:21 pm
NRA Member: yes
Military: yes
Carry Permit: yes
Favorite Firearm: 1874 Sharps
Favorite Ammo: Lapua

Re: Scope for 50 BMG & 338 Lapua

Postby flyjets » Tue 01 Mar, 2011 5:43 pm

ERSC

Unfortunately it doesn't work out exactly that way it's close but at the upper limits
sometimes there might be more down then up adjustment.

Sounds like you got the idea. The NXS series is setup more as a tactical scope larger knobs larger numbers faster focus and Zoom. All around heavier duty construction.

The BR Model is for a Gun that is pampered and not subjected crawling around a field it's a great scope but It is what it names implies a Benchrest scope.

Here is a photo that might help.

DSC01540 (640x480).jpg


Here is the NXS on another Rifle you can see it's Robust construction.

DSC01540 (640x480).jpg


Ian
You do not have the required permissions to view the files attached to this post.
Management is doing things right; leadership is doing the right things.
User avatar
ersc
Active Poster
Posts: 68
Joined: Mon 20 Apr, 2009 4:20 pm
NRA Member: yes
Military: yes
Location: Minnestoa

Re: Scope for 50 BMG & 338 Lapua

Postby ersc » Tue 01 Mar, 2011 7:24 pm

Hi flyjets

This is very helpful... I put together a spreadsheet that looks at MOA and scope range...

The Nightforce 32x and my old Burris XTR seem to good adjustment towards the end of the extreme range of 50 BMG ans 338 Lapua.

I am starting to lean towards the 32x

Image
[ 50 BMG Cooridnator for my loccal sportsman's club -- Retired Navy ] Men trained in arms from their infancy, and animated by the love of liberty, will afford neither a cheap or easy conquest. Declaration of the Continental Congress, July 1775
User avatar
flyjets
Member
Posts: 245
Joined: Mon 20 Apr, 2009 12:21 pm
NRA Member: yes
Military: yes
Carry Permit: yes
Favorite Firearm: 1874 Sharps
Favorite Ammo: Lapua

Re: Scope for 50 BMG & 338 Lapua

Postby flyjets » Wed 02 Mar, 2011 11:15 am

ERSC

I might have given you a false impression.

The purpose of the MOA + 20 Rail is to basically allow you to take advantage of the full use of the elevation adjustment of the scope.

It basically allows you to almost bottom the scope at 100 yards. then use the full UP adjustment to click out 40MOA.
Without the 20MOA Base installed your scope if it's the 12 *42 would only allow an additional 20 MOA adjustment.
Note the above is for the BR model.

Do you see what I am getting at ???

Take the 8 * 32 NXS now it has a 65 MOA total adjustment. but unless you use a rail the up elevation is only 32.5MOA with the addition of the 20 MOA you now have roughly 52.5MOA in 338 Lapua that takes you out to approximately 1400 yards.

Sorry if I might have confused you.

Ian
Management is doing things right; leadership is doing the right things.
User avatar
ersc
Active Poster
Posts: 68
Joined: Mon 20 Apr, 2009 4:20 pm
NRA Member: yes
Military: yes
Location: Minnestoa

Re: Scope for 50 BMG & 338 Lapua

Postby ersc » Thu 03 Mar, 2011 11:54 am

Hi flyjets

Your have been very help!!!

Do these number look resonable? Scope total (MOA/2)+ Rail MOA


Image
[ 50 BMG Cooridnator for my loccal sportsman's club -- Retired Navy ] Men trained in arms from their infancy, and animated by the love of liberty, will afford neither a cheap or easy conquest. Declaration of the Continental Congress, July 1775
User avatar
flyjets
Member
Posts: 245
Joined: Mon 20 Apr, 2009 12:21 pm
NRA Member: yes
Military: yes
Carry Permit: yes
Favorite Firearm: 1874 Sharps
Favorite Ammo: Lapua

Re: Scope for 50 BMG & 338 Lapua

Postby flyjets » Thu 03 Mar, 2011 8:53 pm

ERSC

I sent you 2 excel files that should help if you need more just ask.

Ian
Management is doing things right; leadership is doing the right things.
User avatar
ersc
Active Poster
Posts: 68
Joined: Mon 20 Apr, 2009 4:20 pm
NRA Member: yes
Military: yes
Location: Minnestoa

Re: Scope for 50 BMG & 338 Lapua

Postby ersc » Mon 11 Apr, 2011 10:55 pm

Well I now have a Nightforce 5.5-22 x 56 NXS and Barrett Zero-gap rings (high) sitting on my desk...

I plan to mount it on my Barrett M99... The scope from the Barrett is going on the 338 Lapua...

Has anyone lapped Barrett Rings for this type of set-up?
[ 50 BMG Cooridnator for my loccal sportsman's club -- Retired Navy ] Men trained in arms from their infancy, and animated by the love of liberty, will afford neither a cheap or easy conquest. Declaration of the Continental Congress, July 1775
User avatar
Shadow
Continuing Member
Posts: 817
Joined: Mon 20 Apr, 2009 7:10 pm
NRA Member: yes
Military: yes
Law Enforcement: yes
Carry Permit: yes
Favorite Firearm: Any .50BMG Barrett
Favorite Ammo: API, of course
Location: Not sure, checkin GPS

Re: Scope for 50 BMG & 338 Lapua

Postby Shadow » Tue 12 Apr, 2011 5:15 pm

ersc wrote:Well I now have a Nightforce 5.5-22 x 56 NXS and Barrett Zero-gap rings (high) sitting on my desk...

I plan to mount it on my Barrett M99... The scope from the Barrett is going on the 338 Lapua...

Has anyone lapped Barrett Rings for this type of set-up?


UNLESS you have ultra precision tools (lapping bar, etc) and are very skilled at lapping, I'd suggest NOT lapping the Barrett Rings for use with your Nightforce scope.

The Barrett Zero-gap rings are manufactured from 7075 aluminum alloy. [See Note, below.] IF you lap the aluminum rings you run the risk of removing the "final" finish. Steel rings are another discussion.

Anyway, In almost ALL cases high quality scope rings DO NOT require lapping. You have about a 99% chance of making circular dimensions/alignment worse. Chinese rings used on Chinese Scope tubes are another discussion, also.

I've generally mount scopes (exclusively) with Barrett, Leupold, Warne or Badger Ordance Rings. After checking them, I've never felt a requirement to Lap the rings. YMMV....

Note: Aluminium alloy 7075 has zinc as the primary alloying element. It is strong, with a strength comparable to many steels, but has less resistance to corrosion than many other Al alloys. If "the finish" is removed, corrosion issues may surface.
ImageImageImageImage
User avatar
ersc
Active Poster
Posts: 68
Joined: Mon 20 Apr, 2009 4:20 pm
NRA Member: yes
Military: yes
Location: Minnestoa

Re: Scope for 50 BMG & 338 Lapua

Postby ersc » Thu 21 Apr, 2011 2:32 am

Hi Folks

Thanks for the help...

Mounted my new Nightforce 5.5-22 x 56 NXS and Barrett Zero-gap rings on my Barrett M99 tonight...

I put the Wheeler Engineering scope alignment tool into the rig and the alignment was perfect...

Question: The front bell of the 5.5-22 x 56 NXS has a very small clearance between the rail and the scope...

It is about 5 sheets of paper in thickness... Since the M99 is so rigid this should not be a problem???

I don't think the recoil from the shoot and reverse impulse from the muzzle brake should make things flex and impact...

What are your thoughts????

Thanks

Image
[ 50 BMG Cooridnator for my loccal sportsman's club -- Retired Navy ] Men trained in arms from their infancy, and animated by the love of liberty, will afford neither a cheap or easy conquest. Declaration of the Continental Congress, July 1775
User avatar
Shadow
Continuing Member
Posts: 817
Joined: Mon 20 Apr, 2009 7:10 pm
NRA Member: yes
Military: yes
Law Enforcement: yes
Carry Permit: yes
Favorite Firearm: Any .50BMG Barrett
Favorite Ammo: API, of course
Location: Not sure, checkin GPS

Re: Scope for 50 BMG & 338 Lapua

Postby Shadow » Thu 21 Apr, 2011 10:56 pm

ersc wrote:Hi Folks
Question: The front bell of the 5.5-22 x 56 NXS has a very small clearance between the rail and the scope...

It is about 5 sheets of paper in thickness... Since the M99 is so rigid this should not be a problem???
What are your thoughts????
Thanks

Image


I think a little more clearance would be prudent.

But.... B4 getting the next size rings - mount your rings 180deg from how you have them mounted. :det:
You have Barrett Zero-gap rings. Break out the instructions that came with the rings.....and follow em closely when you remount your rings.

The rings should be mounted so the nuts are on the left side (opposite side from the bolt). They may then align so the front of the scope is a little higher.

If the bell is still that close to the rail, I'd get the next size rings. I doubt if the scope/rail on the 99 will flex much, but I've seen videos where they actually did flex and touch each other.

BTW - With a 56mm Bell, the correct Zero-gap Barrett rings are the ULTRA High rings. I believe you have the HIGH rings.
Good luck...
:D
ImageImageImageImage

Return to “Scopes & Mounts”

Who is online

Users browsing this forum: No registered users and 0 guests