Here is a gun magazine for HK 300 guns. This is a 10 round gun magazine is manufactured New in California. Great gun mag at a great price. Made in the usa by Tripe K from heat treated steel and has a steel floor plate and follower. Spring is made from carbon steel. Gunclip Depot has the largest selection of H&K magazines and gun clips. If you do not see the gun magazine you are looking for send us an email and we will try to locate it for you. Orders shipped within 24 hours except for week-ends and holidays.