PDW Stocks for AR-15s: Short Stocks Explained

Short answer: a PDW stock is a very short telescoping stock that makes an AR-15 more compact. The ones we track add about 5.3 to 6.9 inches behind the receiver when collapsed and reach about 10 inches extended. The key question is the buffer: the Armaspec XPDW fits a standard mil-spec tube with your own parts, while Maxim's CQB stocks and LWRC's compact kit use their own matched systems. On a barrel under 16 inches, any stock makes the rifle a short-barreled rifle under federal law.

How short they get

The three types

Fits a standard tube

The Armaspec XPDW Gen 2 mounts on any standard mil-spec buffer tube with no modification, so you keep your buffer and spring. Armaspec lists 6.875 inches collapsed, 10 inches extended and 16.6 ounces, in aluminum with hardened steel guide rods and an ambidextrous latch. For tube differences, see buffer tube types.

Matched buffer system

Maxim Defense's CQB stock has no button: you pull it to deploy, with four positions. The Gen 7 runs 5.3 to 10 inches and 18.5 ounces per Maxim. It works with Maxim's buffer and spring options, including a 9mm version and a JP Silent Captured Spring option. Retailers disagree on what fits with standard tube parts, so buy the matched set and check Maxim's spec sheet for your gun.

Compact stock kit

LWRC's UCIW stock kit is a milder option: LWRC says it shortens overall length by one inch, and it includes the stock, receiver extension, index plate, buffer, spring and castle nut, designed to work together. It has four positions.

Why the buffer matters

A shorter tube leaves less room for the carrier and spring, so the system has to be matched, and it changes how the rifle cycles. Use the buffer and spring the maker specifies, then test with your ammunition and gas setup. See buffer weights and the AR-9 guide if you are building a pistol-caliber gun, since 9mm uses different buffers.

Stock or brace: the legal line

Checked 30 October 2026; this is general information, not legal advice. Federal law treats a rifle with a barrel under 16 inches, or under 26 inches overall, as a short-barreled rifle. A PDW stock on a 16-inch rifle is an ordinary rifle. On a shorter barrel it is an SBR, and those rules changed in 2026: see short-barreled rifles explained. Some products with PDW in the name are arm braces, not stocks; see how to build an AR pistol. State laws can be stricter, including on adjustable stocks: see California, New York and New Jersey.

Pros and cons

• Pro: a much shorter rifle for storage, vehicles and tight spaces.
• Pro: fast to deploy, especially designs with no button.
• Con: small butt pad and less cheek surface than a full stock.
• Con: buffer system choices narrow on matched designs.

For a full-size option, see the best AR-15 stocks; to shorten a rifle by folding instead, see folding stock adapters.

PDW and compact stocks in stock, with today's prices

Lowest price across the stores we track:

Add one to your rifle in the AR-15 builder, or browse all AR-15 stocks.

Frequently asked questions

What is a PDW stock?

A very short telescoping stock that shrinks an AR-15 when collapsed. PDW stands for personal defense weapon.

Do PDW stocks need a special buffer?

Some do. The Armaspec XPDW fits a standard mil-spec tube with your own parts. Maxim's CQB uses its own buffer and spring options.

Are PDW stocks legal?

On a rifle with a barrel of 16 inches or more and 26 inches overall, federally yes, though some states restrict adjustable stocks. On a shorter barrel a stock makes it a short-barreled rifle.

Is a PDW stock the same as a PDW brace?

No. A stock goes on a rifle; a brace goes on a pistol. Some products share the PDW name, so check the listing.

How long is a PDW stock?

The Maxim CQB Gen 7 runs 5.3 to 10 inches and the Armaspec XPDW Gen 2 runs 6.875 to 10 inches, per the makers.