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Low Friction · August 18, 2013, 10:15 AM

The 32 H&R Magnum CB Limited uses roughly the same receiver, barrel, and bolt as the other CB Limited chamberings. Of course the 32 variant has a really hefty barrel wall thickness as compared to the 44 and 45 models.

Here are some numbers to compare the radial chamber and bolt face pressures for the 327mag and the 44mag at peak SAAMI pressures.

327 fed mag/44mag
Bolt face area: 0.089 in^2/0.163 in^2
Radial chamber area: 1.220 in^2/1.750 in^2
SAAMI max pressure: 45,000 psi/36,000 psi
Bolt face pressure: 4005 lbs/5868 lbs
Radial chamber pressure: 54,900 lbs/63,000 lbs

The cumulative radial chamber pressure is ~15% higher for the 44mag that has a substantially thinner barrel compared to the 32 h&r. The cumulative bolt face pressure is a whopping 46% higher for the 44mag. I'm pretty comfortable with the design margin.

August 18, 2013, 10:15 AM	#956
Low Friction Member Join Date: May 30, 2011 Location: Seattle Posts: 69	The 32 H&R Magnum CB Limited uses roughly the same receiver, barrel, and bolt as the other CB Limited chamberings. Of course the 32 variant has a really hefty barrel wall thickness as compared to the 44 and 45 models. Here are some numbers to compare the radial chamber and bolt face pressures for the 327mag and the 44mag at peak SAAMI pressures. 327 fed mag/44mag Bolt face area: 0.089 in^2/0.163 in^2 Radial chamber area: 1.220 in^2/1.750 in^2 SAAMI max pressure: 45,000 psi/36,000 psi Bolt face pressure: 4005 lbs/5868 lbs Radial chamber pressure: 54,900 lbs/63,000 lbs The cumulative radial chamber pressure is ~15% higher for the 44mag that has a substantially thinner barrel compared to the 32 h&r. The cumulative bolt face pressure is a whopping 46% higher for the 44mag. I'm pretty comfortable with the design margin. Last edited by Low Friction; August 19, 2013 at 05:37 PM.