5/16" Springs | McMaster-Carr

Press these catches into a hole. A countersunk indentation acts as a stop for ball-nose spring plungers. Also known as ball buttons, they withstand side loads to prevent fixture damage. Made from 440C stainless steel, they're mildly chemical resistant and may be mildly magnetic.

				440C Stainless Steel
For Nose Dia.	Lg.	OD	Detent Dia.		Each
0.156"	5/16"	0.266"	0.139"	00000000	00000

Slotted Spring Pins


	End View

Squeeze these pins into holes and they expand slightly, creating tension to hold parts in place. They are often used as hinge pins and as fasteners for springs and power transmission components. An alternative to dowel pins, they're lighter in weight with a hollow center and don’t need a precise hole. Also known as roll pins.

Spring Steel—These pins won't deform from stress and vibration. Although they're stronger than stainless steel, they're best for dry environments since moisture will cause them to rust.

Zinc-Plated Spring Steel—These pins withstand occasional exposure to moisture. However, since friction from moving parts can wear away the finish, they're not ideal for wet environments. While not nearly as corrosion resistant as stainless steel, they are stronger and won’t deform under stress.

Corrosion-Resistant 18-8 Stainless Steel—The choice for wet and outdoor environments, these pins resist rusting. They are strong enough to join most components but won't withstand extreme stress and vibration as well as steel.

Highly Corrosion-Resistant 316 Stainless Steel—Superior to 18-8 stainless steel, these pins won't degrade when exposed to harsh weather, salt water, and most chemicals. They're strong enough to join most components but won't withstand extreme stress and vibration as well as steel.

Wear-Resistant 400 Series Stainless Steel—Our most wear-resistant stainless steel pins, these are good for pivoting parts that create a lot of friction. They hold up in environments that experience occasional moisture, but they're not as corrosion resistant as 18-8 and 316 stainless steel.

	For Hole Dia.	Wall Thk.	Double Shear Breaking Strength, lbf	Min. Hardness	Specs. Met	Pkg. Qty.		Pkg.
Spring Steel







			1/16" Diameter

			5/16"	0.062" to 0.065"	0.012"	430	Rockwell C43	ASME B18.8.2	500	000000000	000000




					5/64" Diameter

					5/16"	0.078" to 0.081"	0.018"	800	Rockwell C43	ASME B18.8.2	250	000000000	00000




							3/32" Diameter

							5/16"	0.094" to 0.097"	0.022"	1,100	Rockwell C43	ASME B18.8.2	500	000000000	00000




									1/8" Diameter

									5/16"	0.125" to 0.129"	0.028"	1,800	Rockwell C43	ASME B18.8.2	500	000000000	00000


									Zinc-Plated Spring Steel







													1/16" Diameter

													5/16"	0.062" to 0.065"	0.012"	430	Rockwell C43	ASME B18.8.2	500	000000000	00000




															5/64" Diameter

															5/16"	0.078" to 0.081"	0.018"	800	Rockwell C43	ASME B18.8.2	250	000000000	00000




																	3/32" Diameter

																	5/16"	0.094" to 0.097"	0.022"	1,100	Rockwell C43	ASME B18.8.2	250	000000000	00000




																			1/8" Diameter

5/16"																			0.125" to 0.129"	0.028"	1,800	Rockwell C43	ASME B18.8.2	250	000000000	00000


Corrosion-Resistant 18-8 Stainless Steel







																			1/16" Diameter

			5/16"																0.062" to 0.065"	0.012"	250	Not Rated	ASME B18.8.2	100	000000000	0000




																			5/64" Diameter

					5/16"														0.078" to 0.081"	0.018"	450	Not Rated	ASME B18.8.2	100	000000000	0000




																			3/32" Diameter

							5/16"												0.094" to 0.097"	0.022"	650	Not Rated	ASME B18.8.2	100	000000000	0000




																			1/8" Diameter

									5/16"										0.125" to 0.129"	0.028"	1,000	Not Rated	ASME B18.8.2	100	000000000	0000


									Highly Corrosion-Resistant 316 Stainless Steel







																			1/16" Diameter

													5/16"						0.062" to 0.065"	0.012"	200	Not Rated	ASME B18.8.2	100	000000000	00000




																			3/32" Diameter

															5/16"				0.094" to 0.097"	0.022"	600	Not Rated	ASME B18.8.2	100	000000000	00000


															Wear-Resistant 400 Series Stainless Steel







																			1/16" Diameter

																			5/16"	0.062" to 0.065"	0.012"	430	Rockwell C43	ASME B18.8.2	100	000000000	0000




																			5/64" Diameter

	5/16"	0.078" to 0.081"																	0.018"	800	Rockwell C43	ASME B18.8.2	100	000000000	00000




																			3/32" Diameter

			5/16"	0.094" to 0.097"															0.022"	1,100	Rockwell C43	ASME B18.8.2	100	000000000	0000




																			1/8" Diameter

					5/16"	0.125" to 0.129"													0.028"	1,800	Rockwell C43	ASME B18.8.2	100	000000000	00000

Coiled Spring Pins

End View

The best spring pins for joining parts exposed to vibration and shock. They're often used in power transmission, automation, and other assemblies with constant motion and sudden starts and stops. Because of their spiral shape, they flex to conform to holes that aren’t perfectly round.

Spring Steel—These pins won't deform from stress and vibration. Although they're stronger than stainless steel, they're best for dry environments since moisture will cause them to rust.

	Min. Hardness	Specs. Met	Pkg. Qty.		Pkg.
Spring Steel







	1/16" Diameter

	5/16"	0.062" to 0.065"	330	Rockwell C42	ASME B18.8.2	100	000000000	000000




			5/64" Diameter

			5/16"	0.077" to 0.081"	550	Rockwell C42	ASME B18.8.2	100	000000000	0000


			Corrosion-Resistant 18-8 Stainless Steel







							1/16" Diameter

							5/16"	0.061" to 0.065"	265	Not Rated	ASME B18.8.2	50	000000000	00000




									3/32" Diameter

									5/16"	0.094" to 0.097"	600	Not Rated	ASME B18.8.2	25	000000000	0000




											1/8" Diameter

											5/16"	0.125" to 0.129"	1,100	Not Rated	ASME B18.8.2	25	000000000	00000


											Wear-Resistant 400 Series Stainless Steel







															1/16" Diameter

															5/16"	0.061" to 0.065"	330	Rockwell C46	ASME B18.8.2	50	000000000	00000




																	5/64" Diameter

																	5/16"	0.077" to 0.081"	550	Rockwell C46	ASME B18.8.2	50	000000000	00000