The Underwood 9mm Luger +P 124gr XTP JHP (Underwood part no. 134) is a 20 rounds-per-box load built around a Hornady eXtreme Terminal Performance bullet. Underwood Ammo cites the XTP for its power and accuracy, with deep terminal penetration and controlled expansion, in a nickel-plated brass case. The 124-grain bullet leaves the barrel at 1225 feet per second with 413 ft-lbs of muzzle energy. Underwood prints a note on aftermarket Sig P365 conversion barrels for its +P and +P+ 9mm ammunition, covered in the FAQ.

Key Specifications

• The chambering is 9mm Luger +P, the higher-pressure designation Underwood prints for this load.
• The bullet weighs 124 grains, the weight Underwood loads in this XTP.
• The bullet is a Hornady XTP jacketed hollow point, designed for deep terminal penetration and controlled expansion.
• Muzzle velocity is rated at 1225 fps, and Underwood lists this as a supersonic round.
• Muzzle energy is listed at 413 ft-lbs, a figure for comparing this load with other 9mm +P ammunition.
• The case is nickel-plated brass, which Underwood says resists tarnish and eases cleanup during reloading.
• The bullet has a sectional density of 0.141 and a G1 ballistic coefficient of 0.118, the published numbers for this projectile.
• The bullet is 0.355 inch in diameter and is made from copper and lead.
• Underwood uses flash suppressed powder, so your vision is not compromised if you must shoot in low light.
• Each box holds 20 rounds, a count that suits carry and practice.

Frequently Asked Questions

Is this 9mm load +P? Yes. Underwood designates it 9mm Luger +P. Its +P+ 124-grain XTP load is a separate product.

Can I use it with an aftermarket Sig P365 barrel? Underwood says aftermarket Sig P365 conversion barrels are not recommended for use with its +P and +P+ 9mm ammunition, and that all of its testing and validation is performed with factory Sig P365 barrels.

Is it safe in a suppressor? Underwood states that this ammunition is safe to use in a suppressor.

Buy the Underwood Ammo 9mm Luger +P 124gr XTP JHP Ammunition, 20-Round Box

Underwood loads this 124-grain XTP to +P pressure with a Hornady bullet and a nickel-plated case. Order it with other handgun ammunition from our Lubbock, Texas gun shop and it ships fast with insured delivery.