Any reason NOT to go with a 34mm tube size?

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[ARCHIVED THREAD] - Any reason NOT to go with a 34mm tube size?

Posted: 12/26/2023 11:23:56 AM EDT

I'm scope shopping for a MK12/SPR scope. Any reason not to go with a 34mm tube over a 30mm other than cost if all else is equal?

Posted: 12/26/2023 11:26:11 AM EDT

[#1]

Weight?
Reduced scope/ring selection?

Posted: 12/26/2023 11:43:23 AM EDT

[#2]

Weight mainly. What is the purpose for the scope?

Posted: 12/26/2023 12:11:59 PM EDT

[#3]

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Quoted:
Weight mainly. What is the purpose for the scope?

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MK12/SPR. Looking for a mid power/size scope with a mil reticle. Something around 4-14x.

Posted: 12/26/2023 12:20:41 PM EDT

[#4]

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Quoted:

MK12/SPR. Looking for a mid power/size scope with a mil reticle. Something around 4-14x.

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In that case a 30mm tube will suffice

Posted: 12/26/2023 1:26:13 PM EDT

[#5]

If you are looking at the factors of weight, total amount of dialing needed for your task, and durability, I think you can ignore tube dimensions as long as it's 30mm or 34mm.

1", 35mm, and others have a harder time finding a mount so care must be taken.

Posted: 12/26/2023 2:45:44 PM EDT

[#6]

For a bolt action, the 34mm is great. No way would I put one on a AR. To heavy.

Posted: 12/26/2023 2:57:36 PM EDT

[#7]

I looked into one, but I finally have everything in 30mm. Nope.

Posted: 12/26/2023 3:51:49 PM EDT

[#8]

Quote History

Quoted:

MK12/SPR. Looking for a mid power/size scope with a mil reticle. Something around 4-14x.

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Do you need side focus? What's the budget?

Posted: 12/26/2023 4:51:35 PM EDT

[#9]

Weight. More than 30mm is stupid for anything less than 20x.

Posted: 12/26/2023 6:38:16 PM EDT

[#10]

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Quoted:

Do you need side focus? What's the budget?

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I would prefer parallax focus, yes. No budget, but over $1,500 will delay the purchase a bit.

Posted: 12/26/2023 8:11:59 PM EDT

[#11]

I just picked up a Delta Stryker 3.5x21 for my 6.5CM LMT rifle. It's a 34mm tube, and 28oz. That seems pretty in-line with the 30mm tube offerings. The Leupold MK5HD is 35mm and 26oz.

Posted: 12/26/2023 9:08:22 PM EDT

[#12]

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Quoted:

I just picked up a Delta Stryker 3.5-21x44 -snip-

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Posted: 12/26/2023 9:16:09 PM EDT

[#13]

It's going to require rings or a mount which is at least 2mm higher. I have a US Optics FDN 10X which is 34 mm, my older low rings from my ST-10 30mm didn't work.

Posted: 12/26/2023 10:21:25 PM EDT

[#14]

Quote History

Quoted:
It's going to require rings or a mount which is at least 2mm higher. I have a US Optics FDN 10X which is 34 mm, my older low rings from my ST-10 30mm didn't work.

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It makes perfect sense that your 30mm rings didn’t work with a scope that has a 34mm tube

Posted: 12/27/2023 12:43:44 AM EDT

[#15]

If you shop around and check places like euro optic , midway , sport optics you might be able to find a vortex gen 2 viper 3x15x44 at about 40% off retail . I picked on up and the only reason they are on close out is a slight change in the reticle . 30 mm tube and plenty of elevation your not going to run out of elevation before your 5.56 run's out of steam .

Posted: 12/27/2023 10:06:30 AM EDT

[#16]

Quote History

Quoted:
If you shop around and check places like euro optic , midway , sport optics you might be able to find a vortex gen 2 viper 3x15x44 at about 40% off retail . I picked on up and the only reason they are on close out is a slight change in the reticle . 30 mm tube and plenty of elevation your not going to run out of elevation before your 5.56 run's out of steam .

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I was looking at these. There are actually not a lot of options as far as turrets, parallax and reticle withing the power range I'm looking for that are 30mm except the Vortex. Other scopes that fit the bill but are 34mm are the new PA GLx 3-18 44 and the Nightforce ATACR 4-16 42.

Posted: 12/27/2023 10:56:07 AM EDT

[#17]

Quote History

Quoted:
If you shop around and check places like euro optic , midway , sport optics you might be able to find a vortex gen 2 viper 3x15x44 at about 40% off retail . I picked on up and the only reason they are on close out is a slight change in the reticle . 30 mm tube and plenty of elevation your not going to run out of elevation before your 5.56 run's out of steam .

View Quote

Do the turrets lock on the Vortex gen 2 viper?

Posted: 12/27/2023 2:36:52 PM EDT

[#18]

For your purpose, I think there's not much advantage to a 34mm tube. 30mm will be sufficient.

Here's a like new in box Vortex Viper PST Gen II 3-15x44 with the EBR-4 reticle for about $720.00. It does not have locking turrets.

Posted: 12/28/2023 2:09:33 AM EDT

[#19]

Quote History

Quoted:
It's going to require rings or a mount which is at least 2mm higher. I have a US Optics FDN 10X which is 34 mm, my older low rings from my ST-10 30mm didn't work.

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Optic centerline height was likely the least of your worries trying to fit a 34mm main tube scope in 30mm rings.

Posted: 12/28/2023 2:11:55 AM EDT

[#20]

I wouldn’t make main tube size a determining factor personally, OP.

Find a scope that meets your needs, has the features you want at the price you want, and go with it.

Posted: 12/28/2023 12:29:14 PM EDT

[#21]

A 34mm tube will allow for a larger erector system and/or a larger adjustment range depending on the overall scope design, but it usually comes with a weight penalty. Adjustment range may matter depending on how far you intend to shoot and the erector size has the potential to impact light transmission and image quality.

My personal approach for scope selection is to identify the important characteristics or features for my intended application and then narrowing my search to scopes that meet my needs. Weight and length are usually considered regardless of my application, but I don't think I have used tube size as a deciding factor.

Basically, find a scope that will perform at a level meeting or exceeding your expectations and then carry on.

Posted: 12/29/2023 5:15:11 PM EDT

[#22]

As others have mentioned a 34mm scope will likely be a little bit heavier than a comparable 30mm one. However, if you’re building a SPR style rifle, weight probably isn’t a huge concern.

I recently put together an 18” SPRish rifle and went with a Steiner T6Xi 2.5-15 which has a 34mm body. I don’t regret using a scope of this size or wish I had gone with a smaller 30mm one.

Posted: 12/29/2023 5:18:44 PM EDT

[#23]

You could go 35mm

Posted: 12/29/2023 5:19:45 PM EDT

[#24]

Buy whatever scope you want.

Posted: 12/29/2023 5:28:40 PM EDT

[#25]

Quote History

Quoted:
A 34mm tube will allow for a larger erector system and/or a larger adjustment range depending on the overall scope design, but it usually comes with a weight penalty. Adjustment range may matter depending on how far you intend to shoot and the erector size has the potential to impact light transmission and image quality.

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Always wanted to know.. does a 34mm tube allow larger glass elements? If yes, is the image clarity better?

Posted: 12/29/2023 9:56:20 PM EDT

[#26]

Quote History

Quoted:

Always wanted to know.. does a 34mm tube allow larger glass elements? If yes, is the image clarity better?

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It took me a minute to find the link, but Leupold seems to think so based on their wording in #1.

Top 5 Optic Myths Explained

"The little-known fact is that it’s the erector system that limits how much light is getting to your eye. It also has a big effect on image quality."

[ARCHIVED THREAD] - Any reason NOT to go with a 34mm tube size?

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