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5/26/2026 7:21:52 AM EDT
I was Wondering if a gen 2 barrel will fit in a gen 3 (spear LT upper). I have An opportunity to get a gen2 barrel at a lower price point than I was looking at.  He might sell me the complete gen 2 upper.  Thanks.

Lastly would a gen 3 barrel fit in a Gen 2 upper?
5/26/2026 8:42:24 AM EDT
[#1]
Originally Posted By aftac:
I was Wondering if a gen 2 barrel will fit in a gen 3 (spear LT upper). I have An opportunity to get a gen2 barrel at a lower price point than I was looking at.  He might sell me the complete gen 2 upper.  Thanks.

Lastly would a gen 3 barrel fit in a Gen 2 upper?
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I don't think the bolts are the same.
5/26/2026 2:09:56 PM EDT
[#2]
He is going to sell me the bolt as well.

5/26/2026 5:29:05 PM EDT
[#3]
The bolts are interchangeable between Virtus and LT.

Legacy variant is a no go.
5/27/2026 9:30:28 AM EDT
[#4]
Originally Posted By aftac:
I was Wondering if a gen 2 barrel will fit in a gen 3 (spear LT upper). I have An opportunity to get a gen2 barrel at a lower price point than I was looking at.  He might sell me the complete gen 2 upper.  Thanks.

Lastly would a gen 3 barrel fit in a Gen 2 upper?
View Quote


Gen 2 (Virtus) & Gen 3 (Spear-LT) barrels and bolts are interchangeable.

Gen 1 barrels will work in Gen 2/3. But would require the non-tapered bolt.
Some people shouldn't own boats. -Hollister
6/28/2026 8:00:51 AM EDT
[#5]
It depends on how you define generation. But the civilian aesthetic generational nomenclature is generally Virtus=Gen2 and Spear-Lt=Gen3.

In reality, many other generations are involved.

All bolts and barrels are cross-compatible across all generations EXCEPT the original Gen-1 and Gen-0 (pre-release) guns. For those, you need the barral with matching bolt.

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