firearmsAR-15custom foam

Custom Foam Inserts for AR-15 Cases: Layout Ideas and Tips

March 30, 2025by CutMyCase

Planning Your AR-15 Foam Layout

The AR-15 platform is endlessly configurable, which makes foam layout planning both important and challenging. A basic carbine has a different profile than a free-floated precision build with a bipod and 1-8x scope. Start by laying out exactly what travels in the case.

Essential Items to Account For

The Rifle

Measure your rifle's total length with the stock extended and collapsed (if applicable). Note the height including optics — a tall scope or red dot on a riser can add 2-3 inches above the rail.

Key dimensions to capture:

Overall length (stock extended)
Height at tallest point (usually the scope)
Width at widest point (usually the handguard or magazine)
Suppressor length if mounted

Magazines

Most AR shooters carry 3-6 magazines to the range. PMAG 30-round magazines need about 3.5 x 1.5 inches each. Plan vertical slots for clean organization.

Optics Not Mounted

If you transport a scope or red dot separately, it needs its own padded cavity. Include lens caps in your measurement.

Support Gear

Bore snake or cleaning rod
Multi-tool or armorer's wrench
Lubricant bottle
Ear protection (electronic muffs need more space)
Eye protection
Extra batteries for optics
Sling (if removed during transport)

Layout Configurations

Single Rifle, Minimal Accessories

Place the rifle diagonally in the case to maximize length. Group magazines along one edge. Accessories fill the remaining corner.

Best cases: Pelican 1700, SKB 3i-3614-6

Single Rifle with Suppressor

A suppressed AR-15 can exceed 40 inches. Use a longer case or transport the suppressor detached in its own cavity.

Best cases: Pelican 1720, Pelican 1750

Two Rifles

A double rifle layout works best with rifles oriented in opposite directions (muzzles at opposite ends). This equalizes weight distribution and maximizes space.

Best cases: Pelican 1750, SKB 3i-5014-6

Range Day Setup

For a full range session, include the rifle, 6 magazines, ear and eye protection, cleaning kit, stapler and targets, and a shot timer. This requires a larger case with organized sections.

Best cases: Pelican 1750, Nanuk 990

Foam Depth Considerations

Bottom Layer (2-3 inches deep)

The rifle and magazines sit in the bottom layer. Cut the rifle cavity to follow the exact profile including the pistol grip, trigger guard, and magazine well.

Top Layer (1-1.5 inches deep)

Accessories, cleaning supplies, and ear protection go in the shallower top layer. This keeps small items from sitting on top of the rifle.

Lid Foam

Keep convoluted (egg-crate) foam in the lid. It provides consistent downward pressure on everything in the case and accommodates optic height variations.

Pro Tips

Finger Pulls

Add a scalloped cutout near the pistol grip and another near the handguard. This makes it easy to lift the rifle out of a snug cavity.

Magazine Orientation

Stand magazines upright with the feed lips facing up. This makes them easy to grab and prevents the feed lips from pressing against foam.

Zero Protection

If you've zeroed your optic, foam fit around the scope is critical. Any movement during transport can shift zero. A custom contour around the scope body and turrets locks it in place.

Get Your AR-15 Foam Cut

Take a photo of your AR-15 with all accessories laid out. CutMyCase AI generates an exact outline of the rifle profile — including your specific optic, light, and grip configuration. Design your layout and we'll precision-cut the foam.