Bed It Right! Bedding Compounds Compared by Speedy

A customer of well-known gunsmith (and Hall-of-Fame shooter) Thomas “Speedy” Gonzalez recently asked Speedy about bedding compounds. Speedy offered some interesting advice based on long-term testing of various materials. Speedy favors Marine-Tex because it is very stable over time, while other materials can shrink up to 6% dimensionally. A good bedding job should be a perfect fit to your barreled action. If the bedding material shrinks over time, that is NOT a good thing….

Speedy’s customer asked: “I know you’re not a Devcon man in regards to bedding compounds but I respect your input in such matters and my question is this in regard to aluminum actions. If Devcon was considered, for an aluminum action, would you prefer aluminum compound formula or steel formula? I personally prefer Devcon steel and Marine-Tex for steel receivers but my experience with aluminum is limited. Also do you have a release agent preference that works better with aluminum?”

Speedy answered: “My only preference of one epoxy over another is their stability over time. My buddy who works for the Texas State Weights and Measures Department had me cast several of the most common types of epoxies used for bedding into 1.000″ machined blocks. After one year of being kept in a controlled climate and measured for shrinkage monthly, the Marine Tex shrunk only 1/10th of 1% (i.e. 0.1%) whereas almost all the others (including Devcon Steel formula, Devcon Aluminum formula…) shrunk 3% to 6%. The only other compounds that matched the Marine Tex were Araldite 1253 and Araldite 2014, with the latter being quite expensive for daily use.”

Speedy added: “The Marine Tex Grey has no atomized metal in its makeup even though it appears that it does. This can be proven by the use of a strong neodymium magnet. What is humorous to me is that people don’t like aluminum yet will bed their actions atop aluminum pillars that have twice the coefficient of expansion (COE) of steel. Like Devcon, it is what people have always done and used. Thus [they] perpetuate the same old stuff. That’s my two cents’ worth. But as I tell everyone, ‘I’ll tell you what I know or do, but it’s not my job to convince anyone to do it my way’.”

Release Agents — Try Shoe Polish
Regarding release agents, Speedy stated: “I use Kiwi Neutral or Tan shoe polish. This works great and you can find it anywhere. Do NOT use the black or brown as it will stick.”

View More Photos of Speedy Inletting and Bedding Job
CLICK HERE to see an interesting bedding job done by Speedy using a custom titanium bedding block. Speedy notes, “The stock was a raw blank requiring full inletting for the action to fit properly plus the titanium block. All the loading ports, bolt handle cut, bolt stop, and trigger guard cuts were done with diamond tooling to eliminate fraying and/or delamination of the wood.” You’ll find more projects by Speedy on his Facebook Page. Speedy is in San Antonio, Texas now, and accepting new projects with his company S.G. Rifles LLC.