The C7 is the Canadian version of the M16 and has the Colt model number R715. The C7 is based on the M16A1, but features many improvements found on the M16A2. These improvements included a heavier barrel and rifling twist rate for the 5.56x45mm NATO round. Unlike the M16A2 used by US forces the C7 is capable of fully automatic fire. The C7 has a fixed metal handguard with M16A1-type iron sights. The more common C7A1 has a flat top receiver that is fitted with a Weaver accessory rail that allows optics to be mounted. Originally the C7A1 was known as the C7 Flat Top, or C7FT.

The C7A2 is an improved model of the C7A1 and features a variety of upgrades. The C7A2 is fitted with the retractable stock of the C8 carbine, has ambidextrous controls, a green furniture and additional accessory rails. The orignal Weaver rail is replaced by a Picatinny rail, which has become the international standard for mounting accessories.

The C7 NLD is a similar upgrade for the Ducht forces. The modifications include a retractable stock, a variety of accessory rails, a tactical light, a grippod and new optics.

The C8 is the Canadian counterpart of the American CAR-15 carbine and has the Colt model number R725. Compared to the C7 the C8 features a retractable stock and shorter barrel and handguard. The C8A1 has a flat top receiver with Weaver accessory rail instead of a carrying handle. Originally the C8A1 was known as the C8 Flat Top, or C8FT. The C8 and C8A1 feature the thin barrel profile of the CAR-15, but with rifling for NATO ammunition. The C8 Heavy Barrel, or C8HB, has the same thicker step cut barrel as the American M4 carbine. The C8HB is now known as the C8A2.

The C8 Special Forces Weapon was developed for special forces use. The C8 SFW has a longer, stepped barrel that thickens near the muzzle. This results in a longer effective range while retaining the compactness of the C8. The C8 CQB is a subcompact version of the C8 with a very short barrel. Only the flash hider and front side protrude from the handguard.

The C7 Light Support Weapon is a co-development between Diemaco and Colt. Unlike the heavy barrel M16A1 it is more than a simple modification of the baseline assault rifle. The C7 LSW has a fixed heavy hammer forged barrel that is encased in a large square handguard. The rate of fire is lowered and a bipod is fitted. Early versions had a bipod near the muzzle and fired fully automatic only. Later versions have the bipod placed under the handguard, also allow for semi-automatic fire and feature accessorry rails near the front sight. The C7 LSW has a fixed sights and the C7A1 LSW has a flattop mount similar to the C7A1. Colt sells the Canadian produced C7 LSW with Colt markings as the M16A2 HB R750.

The C8 Custom Tactical, or C8CT for short, is a designated marksman version of the C8 carbine. It features a free floating heavy barrel and fires semi-automatic only. The C8CT is very ergonomic with double stage trigger, a contour pistol grip with palm rest and an adjustable stock derived from the C8.

The C7 Custom Tactical, or C7CT for short, is a designated marksman version based on the C7 rifle. It features a free floating heavy barrel and fires semi-automatic only. It features a two stage trigger, a bipod, an optional silencer and a pistol grip with palm rest and is normally fitted with high powered optics.