The PTR VENT Spiritus 5.56i suppressor is a compact, hard-use 5.56 can with an approximately 6-inch monolithic body 3D printed from Inconel (brand part no. VS-5560101). PTR positions it as the shorter, tougher counterpart to the titanium VENT 3, trading some weight for a material chosen for strength and resistance to the extreme heat of demanding firing schedules. Purposely Induced Porosity (PIP) and radial PIP venting manage gas and limit the pressure that drives gas to the shooter’s face on semiautomatic rifles. PEW Science recorded Suppression Ratings of 37.5 on a 10.3-inch MK18 and 44.2 on a 14.5-inch M4A1.

Key Specifications

• PTR lists the calibers as 5.56x45mm NATO, 5.7x28mm and 4.6x30mm.
• The minimum barrel length is 10.5 inches for 5.56x45mm, with none specified for 5.7x28mm and 4.6x30mm.
• Length is 6 inches without the adapter, compact for a hard-use 5.56 can.
• Weight is 15.2 ounces without the adapter, the trade for the tougher material.
• Diameter is 1.625 inches, as PTR lists it.
• Construction is 3D-printed Inconel, a high-temperature alloy chosen for durability.
• The finish is black diamond-like carbon (DLC), a hard coating for wear resistance.
• The mount is a 1-3/8×24 HUB interface, with a 1/2×28 direct-thread adapter included.
• Gas management uses PIP with radial venting, which keeps flow moving through the suppressor.
• PTR gives it a full-auto rating, reflecting the heat tolerance of the Inconel core.

Frequently Asked Questions

How does the Spiritus compare with the VENT 3? PTR calls it the compact, hard-use counterpart to the titanium VENT 3: shorter overall, made from Inconel for durability, and heavier at 15.2 ounces versus the VENT 3’s 11.75 ounces.

Do I need ATF approval to buy this? No. As of October 9, 2026, ATF no longer requires Form 4 approval, registration or a tax stamp for suppressors. It transfers on a Form 4473 with a background check through a Class 3 (SOT) dealer. State and local laws still apply.

What is the minimum barrel length? PTR specifies a 10.5-inch minimum for 5.56x45mm and none for 5.7x28mm or 4.6x30mm.

Buy the PTR VENT Spiritus 5.56i Suppressor, Black Inconel, HUB Mount

As of October 9, 2026, this suppressor transfers on a Form 4473 with a background check at your Class 3 (SOT) dealer, with no Form 4 or tax stamp; state and local laws still apply. Order through PTR‘s silencers and suppressed firearms lineup and our Lubbock, Texas team will handle the transfer, and it ships fast to your Class 3 dealer.