As indicated in paragraph two of our warranty statement, after-sale modifications will void the warranty for your Beretta product, to the extent that the modification affects the product. (For example, a change in grips on a Beretta pistol will not void the warranty for the front sight, but if the new grips interfere with the movement of the slide when the pistol is fired, any adverse effect on the pistol caused by that interference will not be covered by Beretta's warranty). If you are having trouble with your firearm (as a result of custom modification), Beretta will review the firearm and prepare a quotation for the repair. We may be limited to the services offered due to the modifications which have been performed. In some circumstances, replacement of the firearm may become necessary. If caused by custom modification, the cost of replacement is the responsibility of the owner. This statement also applies to any product manufactured or imported by a subsidiary of Beretta Holding, such as Sako and Tikka. Additionally, modifications, such as aftermarket barrel threading, will void the 1 MOA accuracy guarantee. In this case, the owner would have to purchase a new firearm, as Sako and Tikka do not export individual barrels. In conclusion, it is generally the policy of Beretta USA to recommend that the firearm not be modified beyond factory original specifications. Exceptions to this rule include O/U shotgun barrel fitting (should be done ONLY by a Beretta Authorized Service Center), or kits/parts manufactured and marketed by Beretta USA (e.g. .22LR conversion kits). NOTE: Modification(s) of a firearm that are completed with Beretta marketed parts and kits (e.g. conversion kits) may still void the warranty, if the improper use/installation of these products (conducted by owner or out-of-network gunsmith) creates results that are adverse to function. Services are best conducted by Beretta Authorized Service Centers to ensure that the warranty remains intact.